Patent Publication Number: US-8983996-B2

Title: Assisted searching

Description:
BACKGROUND 
     1. Field 
     The subject matter disclosed herein relates to searching. 
     2. Information 
     Humans continue to generate content, which may include, by way of example, but not limitation, textual content, image content, audio content, video content, or combinations thereof, etc. Collecting, storing, organizing, or accessing content may be problematic due at least in part to the amounts becoming available. 
     To facilitate identification or retrieval, a search resource, such as a search engine, may be provided. A search resource may organize or index content included in large repositories. For example, a user may access a search engine by using a browser executed by a client device. Typically, over a network, the client device is able to communicate with one or more servers that have organized or indexed large amounts of content. A search resource, such as a search engine, may return one or more search results that are based, at least in part, on a search query that may comprise one or more search terms. 
     Unfortunately, if a search query is not formulated appropriately, a search resource may not locate content of interest. Consequently, there are ongoing needs for search resources, for example, to improve search results. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       Non-limiting and non-exhaustive aspects are described with reference to the following figures, wherein like reference numerals refer to like parts throughout the various figures, unless context indicates otherwise. 
         FIG. 1  is a schematic diagram of an example situation in which query recommendations assist a search query, such as in accordance with an embodiment. 
         FIG. 2  is a diagram illustrating an example graphical user interface that may display search results or query suggestions for a search query, such as in accordance with an embodiment. 
         FIG. 3  is a flow diagram that illustrates an example method of implementing assisted searching according to an embodiment. 
         FIG. 4  is a schematic diagram of a system that may be employed to implement an embodiment of assisted searching. 
         FIG. 5  is a schematic diagram illustrating an example situation involving a search query. 
         FIG. 6  is a schematic diagram illustrating competing search paths, such as in accordance with an embodiment. 
         FIG. 7  is a schematic diagram illustrating non-competing search paths, such as in accordance with an embodiment. 
         FIG. 8  is a flow diagram illustrating an example method for generating a metric, such as in accordance with an embodiment. 
         FIG. 9  is a schematic diagram illustrating a possible computing environment that may be employed in connection with an implementation of an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     In the following detailed description, numerous specific details are set forth to provide a thorough understanding of claimed subject matter. However, it will be understood by those skilled in the art that claimed subject matter may be practiced without these specific details. In other instances, methods, apparatuses, systems, or technologies generally that may be known by a person of ordinary skill in the relevant art have not been described in detail so as not to obscure claimed subject matter. 
     A client device may be employed to display a search interface, such as via a browser, for example. Typically, a search interface, such as for a searching resource, including a search engine, associated with one or more servers, for example, may be accessed via a network, such as the Internet, for example, using a browser, such as a web browser. For example, a user may enter a search query comprising one or more search terms to execute a search using the search engine. A search resource, such as a search engine, may return one or more search results. However, depending at least in part upon the search query, it may be that none of the search results are of interest. To continue searching, typically, a request for additional search results may be made based at least partially on one or more earlier-entered search terms or a search may be refined by entering one or more different search terms. However, at some point, a search may be abandoned if the user, for example, in unable to locate search results of interest after several attempts. 
     To facilitate searching, a search resource, such as a search engine, may provide one or more query recommendations, also referred to as a query suggestion, a search suggestion, or simply a suggestion, intended to assist a user to obtain search results of interest. 
     Communication networks, such as local, wide-area, distributed, etc. networks, may provide access to large repositories of stored content. As suggested above, one example comprises the Internet, which has become practically ubiquitous as a source for or as a repository of stored content. The “World Wide Web” (WWW) may comprise at least a portion of the Internet. By way of example, but not limitation, some embodiments are described below in relation to searching the WWW. However, claimed subject matter is not limited in this respect. Instead, embodiments may be implemented with regard to any one of a host of other possible communication networks, including combinations of networks. 
     To provide access to content via a communication network, such as the WWW, tools or services may be provided that facilitate searching of a large amount of content in a reasonably efficient manner. For example, service providers, such as a search engine provider, may enable users to search the WWW or another communication network. 
     A variety of types of content may be made available via the WWW. Examples include text, images, audio, video, games, interactive content, or combinations thereof, etc. Electronically available documents may comprise web pages, files, emails, movies or video clips, pictures, blog entries, or any combination thereof, etc., just to name a few examples. Likewise, electronically available documents may be formulated in accordance with a variety of different formats. Example formats may include, but are not limited to, HyperText Markup Language (HTML), Extensible Markup Language (XML), Portable Document Format (PDF), H.264/AVC, proprietary formats, MPEG, JPEG or combinations thereof, etc., just to name a few. 
     Regardless of format, type of content, etc., a search engine may be employed to identify and gain access to desired content, as previously described. Terms, such as, “search engine”, “search provider”, “search service”, “search interface”, or “search application”, etc. may be used interchangeably, depending at least in part on context. In an example operative usage of a search engine, as previously described, a user may submit a search query via a browser to one or more servers capable of implementing the search engine. In response to a search query, a search engine may return multiple search results. To facilitate access to content that may be of interest, a search engine may rank multiple search results in accordance with an estimate of expected relevancy. 
     To further facilitate access to content that may be of interest, a search engine may also return one or more query recommendations to a user, referred to here as search assistance, as an assisted search, or as an assisted search query. A user may interact with a search result or a query recommendation by, for example, selecting it via some mechanism (e.g., conventionally a user may “clicking” on it by placing a cursor over the item and executing a mouse click, although various other approaches also exist and are included within the scope of claimed subject matter). Another search may be performed and search results may be returned based, at least in part, on selection of a query recommendation. Although selection of a search result may imply high perceived relevance, but it does not necessarily imply high utility or satisfaction. It may therefore be challenging at times to evaluate if search results, whether or not generated using an assisted search approach, may be interest or may improve efficiency in locating content of interest. 
     Providing query recommendations is a well-known technique for search assistance. Nearly all state of the art search engines provide query recommendations. However, approaches do not appear to have considered assistance efficiency, such as reducing time or effort to locate results of interest. Example metrics may include search suggestion click-through-rate (CTR), search query abandonment rate, or an editorial-type metric. Click-type metrics do not usually provide direct evidence of performance. For example, a high CTR may be undercut by a large correlation with a high abandonment rate. For example, users may “click” a query recommendation that may turn out to be a distraction rather than relevant or useful, introducing a potential bias in a metric using CTR. Editorial-type metrics may be designed to provide additional diagnostic information. However, editorial-type metrics may be overly subject specific, relatively costly or relatively slow. In practice, a limited set of query recommendations may be feasibly evaluated with a manual editorial-type metric. Consequently, it may not be affordable to employ editorial-type metrics in a comprehensive manner. 
     In contrast, search path-type metrics may provide advantages over these other approaches. For example, a search path-type metric may provide a measure of efficiency or, conversely, distraction. For example in an embodiment, a path-type metric may be generated based, at least in part, on lengths of chosen search paths. In one or more embodiments, for example, search session logs may be evaluated to identify alternate search paths to a destination and alternate paths may be compared to assess relative efficiency in arriving at the destination. A number of approaches are possible and claimed subject matter is not limited in scope to a particular approach. However, illustrative examples are provided. 
     For example, search queries may be characterized as having an initial or starting query and a destination location. In this context, this may be referred to as reachability of a destination location. Session logs may be evaluated to identify alternate search paths between a start, Q, designating an initiated search query, and a destination location, U, such as, for example, designating a uniform resource locator address, in one possible embodiment. Alternate search paths may be considered to be competitive in that users may traverse alternate paths from Q to U; however, some search paths may be more efficient than others. Likewise, alternate search paths may be partitioned into at least two types: assisted search paths or non-assisted search paths. Assisted search paths may comprise search paths that include traversing (e.g., clicking) one or more query recommendations along the search path. Non-assisted search paths may comprise search paths in which users do not traverse (e.g., click) a query recommendation. A search path length distribution or a time distribution for assisted search paths may be compared to a search path length distribution or time distribution for non-assisted search paths. Likewise, query recommendations corresponding to assisted search paths having a search path time or length distribution that is shorter than an average search path time or length for non-assisted search paths may be considered favorably, for example. Likewise, in an example embodiment, a destination location may be inferred from session logs based at least in part on a user dwell time. Of course, claimed subject matter is not limited in scope in this respect and other approaches are intended to be included within the scope of claimed subject matter. However, a period of time a user dwells on a location presented as part of search query results and selected by a user has been found to be reasonable. For example, without limitation, a threshold time of 100 seconds, as one illustrative example, may be employed. 
     In example embodiments, a search path-type metric may measure performance of one or more query suggestions. For example, as an illustrative example, a metric may be termed a “path gain/loss” (PGL) metric. To calculate a PGL metric, for example, lengths of assisted search paths may be compared to lengths for non-assisted search paths. For example, if an assisted search path has a shorter path time relative to non-assisted search path time, a gain count may be incremented to represent a gain for a clicked search suggestion. If, on the other hand, an assisted search path has a longer path time relative to non-assisted search path time, a loss count may be incremented to represent a loss for a clicked search suggestion. For example, averages for non-assisted search paths may be used in one embodiment. Gains or losses for assisted search paths may be accumulated, such as for multiple alternative search paths, as indicated by search logs, for example. A PGL metric value may be generated based, at least in part, on a gain count or a loss count that may be viewed as indicating efficiency of a query recommendation. Again, this is merely an illustrative example. For example, other embodiments are described in more detail later. It is, of course, intended that claimed subject matter include all such possible embodiments, but not be limited to these illustrative examples. 
       FIG. 1  is a schematic diagram of an example embodiment  100  in which one or more query suggestions or recommendations that correspond to a search query may be provided. As illustrated, embodiment  100  may include search engine  104 , and index  106 . Search engine  104  may include ranking module  110  and assistance module  112 . Assistance module  112  may provide search assistance, such as one or more query recommendations, as described previously, for example. Ranking module  110  may rank search results in terms of relevance, also as described previously. Of course, modules  110  and  112  are provided merely for purposes of illustration. It is not necessary for a search engine to employ separate modules and, of course, claimed subject matter is not limited in scope in this matter; however, solely for purposes of discussion, it may be convenient to refer to modules. It is also noted that any one of multiple possible locations, such as  102   a ,  102   b , and  102   c , may comprise a destination location. Likewise, there may be other locations that are destinations not illustrated and other locations that are not destinations that are not illustrated. These are merely illustrative examples for purposes of discussion. For a search environment that pertains to or facilitates access to web locations, by way of example only, possibilities that are not illustrated may number in the millions, billions, or more. 
     For purposes of discussion, embodiment  100  is illustrated with respect to a search query, such as  114 , search results, such as  116 , search assistance, such as  118 , and additional interactions, such as  120 . Similarly, although a single ranking module  110  and a single suggestion module  112  are shown in  FIG. 1 , claimed subject matter is not limited in this respect. By way of example, but not limitation, search engine  104  may access or retrieve content available at locations  102  and may index the content to generate search index  106 . As described previously, a search query  114  may be transmitted, such as via a browser executing on a client device, to one or more servers, coupled to the client device via a network. The servers may be capable of executing a search engine, for example. Search query  114  may produce search results as a result of execution of search index  106 . Although search index  106  is shown as being separate from search engine  104 , again, none the less, for purposes of convenient discussion, search index  106  may, of course, be fully or partially integrated with search engine  104 . Search engine  104  may employ ranking module  110  to rank search results relative to one another in terms of relevance. A ranked set of search results may be transmitted to user  108  as search results  116 , again via a network coupling a client device to one or more servers (not explicitly shown in  FIG. 1 ) executing the search engine, for example. 
     For an example embodiment, search engine  104  may transmit one or more query recommendations, corresponding to search query  114 , as search assistance  118 . A query recommendation may be generated via any one of a number of approaches. For example, a query recommendation may correspond to a search query based, at least in part, on one or more terms of the search query, on a category of the search query, on search results that are returned responsive to the search query, or any combination thereof, etc., just to name a few examples. A query recommendation or search suggestion may comprise, by way of example, but not limitation, content that is capable of modifying an existing search query or set of search results, content that is capable of initiating a separate search query, or any combination thereof, etc. By way of example only, query suggestions of “San Francisco Giants”, “San Francisco Restaurants”, “San Francisco Jobs”, or “Bay Area” may correspond to a search query for “San Francisco.” However, claimed subject matter is not limited to any particular examples or example attributes for query recommendations or suggestions. 
     In an example embodiment, if a user selects a query recommendation, for example, a search based at least partially on the search suggestion may be performed. Of course, there are other possible actions by a user. Hence, in a search session, one or more additional interactions  120  may take place, such as after search query  114  has been submitted or after search results  116  have been returned. A search session may conclude, however, if a long period of inactivity occurs. It may be inferred that the user has, in effect, abandoned the search since no search results were of interest after a variety of interactions or attempts to locate content of interest. 
       FIG. 2  depicts an example graphical user interface  200  that may be employed to display search results or query recommendations, such as for a search query, according to an embodiment. Of course, a variety of approaches are possible and  FIG. 2  merely illustrates a possible approach without limitation. As illustrated, interface  200  may include a search entry area  202  or a search button  204 . Interface  200  may also include search results area  206  or search suggestion areas, such as  208   a ,  208   b ,  208   c ,  208   d , for example. Search results  116  (e.g., of  FIG. 1 ) may be displayed at search results area  206 , for example. Query recommendations or search suggestions  118  (e.g., of  FIG. 1 ) may also be displayed, such as via one or more of search suggestion areas  208   a ,  208   b ,  208   c , or  208   d . Of course, content, layout, organization, or any combination thereof, etc. of user interface  200  may differ from that which is shown (e.g., in  FIG. 2 ) or described herein. It is intended that any and all such potential variations are included within the scope of claimed subject matter. 
     In an example embodiment, via a browser, for example, interface  200  may be displayed on a display screen of a client device (not explicitly shown in  FIG. 2 ), for example. Search entry area  202  permits entry of a search query. Search button  204  permits a search to be initiated. A search may be initiated, of course, by any one of a host of approaches. By way of example, but not limitation, examples include: activating a search, commanding that a search be undertaken, selecting a search button entering one or more search terms into a search entry area, pressing an “enter” or “return” key, or any combination thereof, etc. 
     Referring again to  FIG. 2 , a search may have been performed for a search query, or search results may be displayed at search results area  206 . By way of example, but not limitation, a listing of at least a portion of a number of search results (not explicitly shown in  FIG. 2 ) that may be considered relevant may be presented at search results area  206 . Generally, search results include hyperlinks or locations that are capable of being accessed via a client device, such as a browser, through a network. Typically, in accordance with HTTP, for example, via a browser, if a user clicks a hyperlink presented as a search result, the client device browser is re-directed to another device on the network, such as a server, that may correspond to the location. At the location, content may be accessible, such as a web page, an electronic document, an image, an audio or video file, combinations thereof etc. If the accessed content is of interest, the location may comprise a destination location. For example, in one embodiment, if an associated dwell time for the location meets or exceeds 100 seconds, the location may be designated as a destination location for the search query that was initiated. 
     For one or more possible embodiments, query recommendations (e.g., search suggestions  118  of  FIG. 1 ) may be displayed in one or more search suggestion areas, such as  208   a ,  208   b ,  208   c , or  208   d , for example. As shown, interface  200  may include tray search suggestion area  208   a , upper search suggestion area  208   b , lower search suggestion area  208   c , related concept search suggestion area  208   d , or any combination thereof, just to name a few examples. Query suggestions may be displayed a variety of ways. For example, for the embodiment of  FIG. 2 , search suggestions may be displayed in a single search suggestion area, such as upper search suggestion area  208   b . Additionally or alternatively, for the embodiment of  FIG. 2 , search suggestions may be displayed in two or more search suggestion areas, such as  208   a ,  208   b ,  208   c , or  208   d . However, claimed subject matter is not limited to any particular approaches to displaying search suggestions. 
     In another example embodiment, one or more search suggestion areas (e.g., of search suggestion areas  208   a ,  208   b ,  208   c , or  208   d ) may be associated with particular types of search suggestions. Example types of search suggestions may include, but are not limited to, search suggestions that, for example: (1) pertain to one or more particular subject categories (e.g., sports, entertainment, news, finance, real estate, finance, etc.), (2) are tailored to a particular user or a particular search history, (3) relate to a set of identified current trends, (4) relate to a particular set of variables or factors, (5) include terms synonymous with terms of the submitted search query, (6) relate to a particular search suggestion generation procedure, or any combinations thereof, etc. By way of example, search suggestions displayed at tray search suggestion area  208   a  may be associated with recent search trends, search suggestions displayed at upper search suggestion area  208   b  may be associated with terms that are synonymous with those of a submitted search query, search suggestions displayed at lower search suggestion area  208   c  may be associated with terms that match a category for terms of a submitted search query, or search suggestions displayed for related concept search suggestion area  208   d  may be associated with terms that are related to a concept of potential interest to a user or are inferred as of being of potential interest by terms of a submitted search query. However, claimed subject matter is not limited in these respects. 
     For an example embodiment, assistance module  112  (of  FIG. 1 ) may evaluate query recommendations. For example, an evaluation as to whether to provide one or more particular query recommendations may be undertaken. Module  112  may also, in an embodiment, generate search suggestions, for example, as was described with reference to  FIG. 1 , for example. As previously described, of course, a search engine may integrate a capability to perform tasks, such as generating query recommendations or evaluating query recommendations, rather than employing a separate module. Likewise, in an example embodiment, multiple assistance modules or an equivalent may likewise be integrated in an embodiment. 
     A user may interact with search suggestions or search results, such as by selecting one or more of them via interface  200 , as an example. A variety of approaches to making a selection electronically are possible and it is intended that any and all approaches be included within the scope of claimed subject matter. As merely a few possible examples, approaches may include: clicking a mouse, touching, such as with a finger or stylus, speaking voice commands, making gestures/motions, performing keyboard strokes, cursor manipulation, such as“hovering over” to make a selection, or any combination thereof, etc. If a search suggestion is selected, at least a portion of search results that are produced based, at least in part, on the selected search suggestion may be displayed, such as via interface  200 , in an embodiment. Search results from a search query submitted via search entry area  202 , initiated via selection of one or more search suggestions, or combinations thereof, etc. may be displayed at search results area  206  in an embodiment. Likewise, as described previously, for example, one or more search results that are displayed at search results area  206  may also be selected. Examples of approaches in which a selected search result may be displayed to a user, by way of example, but not limitation, may include, for example, via an existing window, via a bubble, via a separately generated window, such as a pop-up window, via a separately generated tab of an existing window, by replacing current content displayed at interface  200 , via placement above or below current content displayed at interface  200 , or any combination thereof, etc. If a selected search result is presented, a period of time during which a user may dwelling on a selected, displayed search result may be monitored. 
       FIG. 3  is a flow diagram  300  that illustrates an example method for implementing an embodiment of assisted search. As illustrated, flow diagram  300  may include any of operational blocks  302 - 306 . Although operations  302 - 306  are shown and described in a particular order, it should be understood that methods within the scope of claimed subject may employ an alternative order or alternative operations. Likewise, for an embodiment, operations of flow diagram  300  may be performed so as to be fully or partially overlapping with each other or other operations not illustrated. In an embodiment, one or more of operations  302 - 306  may be performed at least partially by one or more computing platforms such as distributed system of servers, as one example. 
     At operation  302 , one or more search paths, in this example alternate search paths, between a starting query, Q, and a destination location, U, for example, may be identified. In an example embodiment, search or session logs may, for example, be employed in connection with search path identification. A search path may correspond, by way of example, but not limitation, to a set of selected results (e.g., clicks), including related interactions, between initiating a search query and reaching a destination location. 
     At operation  304 , one or more search suggestions may be evaluated in connection with identified search paths, such as between Q and U. In an example embodiment, alternate search paths between Q and U may be evaluated based, at least in part, on a comparison of path length or duration, as an example. By way of example only, a metric may be generated, such as a PGL metric, for example. 
     At operation  306 , it may be determined whether to provide one or more search suggestions, such as, for example, based, at least in part, on one or more search suggestion evaluations. In an example embodiment, providing a search suggestion may be based, at least partially, on whether the particular search suggestion comprises a lateral search suggestion or a competing search suggestion, for example. However, claimed subject matter is not limited in scope in this respect. As a general proposition, if a search suggestion has a reasonable chance of improving efficiency in terms of reaching a destination location, such as based, for example, at least in part, on an evaluation of alternatives, it may be desirable to provide the search suggestion or query recommendation. 
       FIG. 4  is a schematic diagram of an embodiment of a system that may be employed to implement an embodiment of an assisted search. As illustrated, embodiment  400  may include search resources  402 , communication network(s)  404 , and client resources  406 . Likewise, network resources  408 , and location  102  may be accessible. For example, location  102  may comprise a destination location. Search resources  402  may include search engine(s)  104 , assistance module(s)  112 , processor(s)  414 , database(s)  416 , search log(s)  418 , search path(s)  420 , etc. Likewise, these components may be integrated in various arrangements other than as illustrated. The illustration is provided for convenience of discussion. For example, search engine  104  may incorporate assistance module  112 , as well as search logs and search paths, for example. Likewise, other components not illustrated may be included in an embodiment and illustrated components may be omitted from an embodiment. Client resources  406 , which may, for example, comprise a client device, may, as illustrated, include interface  412  and browser  410 . As discussed for search resources  402 , client resources  406  may alternatively include more, fewer, or different components in other embodiments that are within the scope of claimed subject matter. 
     In an example embodiment, database(s)  416  may store index(s), such as  106  (e.g., of  FIG. 1 ) or search log(s)  418 . Search log(s)  418  may comprise a log of sessions in which search engine (s)  104  are accessed for executing search queries, such as accessed via a client device and network, for example. Typically, for example, as a result of communications between a client device requesting execution of search queries and one or more servers that execute requested search queries and serve search results to a requesting client device, search or session logs are available to search resource providers, for example. Search path(s)  420 , such as alternative search paths for a query Q and destination U, for example, may therefore be identified using search log(s)  418 . 
       FIG. 5  is a schematic diagram illustrating an example situation  500  that may involve a search query, such as in accordance with an embodiment. As illustrated, example  500  may include search query  114 , search path  502 , a destination location  504 , and user interactions  506 . Search path  502  may have a search path length  508 . By way of example only, a search path may begin with a search query, such as  114 , or end with a destination location, such as  504 . 
     A search path  502  may comprise a sequence of clicked or otherwise selected search results that are generated between initiation of search query  114  until reaching destination location  504 . However, one or more interactions  506 , which may, for example, include selecting or clicking a query recommendation, may be included along a search path to a destination location. In an embodiment, for example, search paths may be viewed as comprising algorithmic paths or reformulated paths. In an algorithmic path, search results that are served are selected, such as via clicking, to traverse a search path from initiating a search query to reaching a destination location. In a reformulated search path, a search query may be reformulated as the search path is traversed, such as by selecting a query recommendation or simply by submitting additional search queries, for example. Of course, claimed subject matter is not limited to particular examples of a search path, such as  502 , or user interactions, such as  506 . 
     As previously discussed, for an embodiment, a dwell time may be determined, by way of example only, via inference. For example, in one embodiment, a dwell time of 100 seconds or longer may result in designating a location as a destination location along a search path. A dwell time may be measured from, for example, an approximate time that a search result is selected. Thus, in an example embodiment, if a dwell time corresponding to a selected location meets (e.g., equals or exceeds) a dwell time threshold, the location may be identified as a destination location. However, claimed subject matter is not limited to any particular approach to identifying a destination location. The foregoing is merely an illustrative embodiment. 
     In an example embodiment, a search path  502  may be associated with a search path length  508 , as indicated above. Determination of a search path length  508  may be based, at least in part, on search query  114  or destination location  504 , for example. Search path length  508  may extend, by way of example but not limitation, from initiation of search query  114  to include the end of dwell time for destination location  504  in one possible embodiment. Of course, alternate embodiments are likewise possible, including excluding dwell time or including portions of dwell time that meet a threshold time, as examples. Likewise, in additional embodiments, a search path length  508  may include or exclude time attributable to user interactions that may occur between initiation of a search query and reaching a destination location, for example. It is intended that claimed subject matter include any and all such possible embodiments, whether or not provided as an illustrative example. 
     In an example embodiment, an initial search query that starts a search path may be identified from logs, for example. Likewise, as described, a destination location may be identified. A classifier, for instance, may be trained to identify a destination location, although claimed subject matter is not limited in scope to using a classifier. Likewise, aggregation of search paths corresponding to a query, Q, and a location destination, U, for example, may, in an embodiment, be evaluated to compute statistical estimators, such as mean, median, mode, variance, etc. for search path traversal time, for example. 
     Likewise, path traces may be identified. A path trace may track or indicate a sequence of locations selected or clicked, for example, such as from an initiated query to a destination location, for example. For a click event, for example, a search query, search results, and a selected search result, such as a hyperlink, for example, may be useful for evaluation of search paths, search results, query suggestions, etc. For example, alternative search paths may be identified and counted. Statistical estimators, such as for time duration for path traversal, may be computed. Likewise, abandoned search paths may also be identified. For example, reformulation of search queries multiple times without selecting a search result may be employed to infer abandonment of a search path. Therefore, to evaluate query recommendations, a variety of approaches, such as approaches in which search paths are identified and/or search path length or search path time is computed, may be employed in an example embodiment. 
       FIG. 6  is a schematic diagram  600  illustrating multiple example competing or competitive search paths that may extend between a search query and a destination location, such as according to an embodiment. As illustrated, example graph  600  may include search query  114 , destination location  504 , and multiple search paths  502 . More specifically, example  600  may include three assisted search paths  502   a   1 ,  502   a   2 , or  502   a   3 , which are depicted as solid lines (“AP 1 ”, “AP 2 ”, or “AP 3 ”), or three non-assisted search paths  502   n   1 ,  502   n   2 , or  502   n   3 , which are depicted as dashed lines (“NAP 1 ”, “NAP 2 ”, or “NAP 3 ”). As shown, search paths  502  start from search query  114  and terminate at destination location  504 . 
     For an example embodiment, a search path  502  may comprise an assisted search path  502   a  or a non-assisted search path  502   n . By way of example, but not limitation, an assisted search path  502   a  may comprise a search path  502  that includes a user interaction of selecting a search suggestion. By way of example, but not limitation, a non-assisted search path  502   n  may comprise a search path  502  in which a search suggestion is not selected. 
     As shown, multiple assisted search paths such as,  502   a   1 ,  502   a   2 , or  502   a   3 , may include a corresponding initiated search query  114  and a corresponding destination location  504 . Multiple non-assisted search paths such as,  502   n   1 ,  502   n   2 , or  502   n   3 , may likewise include a corresponding initiated search query  114  and a corresponding destination location  504 . Alternate search paths with corresponding initiated search queries and destination locations are referred to here as competing or competitive since the paths represent alternate paths capable of being traversed between  114  and  504 , for example. However, some paths may be longer in time duration, for example. Likewise, search paths in which search suggestion are selected, such as for assisted search paths, such as  502   a , for example, may be evaluated by reference or comparison with competitive non-assisted search paths such as,  502   n , for an embodiment. 
       FIG. 7  is a schematic diagram  700  illustrating multiple example non-competing or non-competitive search paths that may extend between a search query and destination locations, such as according to an embodiment, for example. As illustrated, example  700  may include search query  114 , destination locations  504 , and search paths  502 . More specifically, example  700  includes two destinations,  504   a  and  504   b . Example  700  also includes three assisted search paths such as,  502   a   4 ,  502   a   5 , or  502   a   6 , which are depicted as solid lines (“AP 4 ”, “AP 5 ”, or “AP 6 ”). As shown, search paths  502  start from search query  114  and terminate at a destination location, such as  504 . For this example, one or more assisted search paths such as,  502   a , may not have corresponding destination locations. Thus, assisted search paths  502   a  may not have a corresponding competitive non-assisted search path. An assisted search path may be considered a non-competitive or non-competing search path if there is no non-assisted search path having a corresponding initiated search query and a corresponding destination location. 
     Assisted search paths such as,  502   a   4 ,  502   a   5 , or  502   a   6 , may, therefore, for an example embodiment, be considered non-competitive search paths. As shown, assisted search paths, such as  502   a   4  or  502   a   5 , may begin with search query  114  and end with destination  504   a . Assisted search path  502   a   6  may begin with search query  114  and end with destination  504   b . Search paths  502   a   4 ,  502   a   5 , or  502   a   6  here are assisted by including selection of a search suggestion during search path traversal between search query  114  and destination  504   a  or destination  504   b . In this context, search suggestions or query recommendations may be categorized in some instances as comprising a lateral search suggestion or a non-lateral search suggestion. As used herein, a lateral search suggestion or lateral query recommendation may comprise a search suggestion or query recommendation that is part of a non-competitive assisted search path. As used herein, therefore, a non-lateral search or query suggestion or a competitive search or query suggestion may comprise a search or query suggestion that is part of a competitive assisted search path. 
     For an example embodiment, metrics may be employed to evaluate search suggestions. Three example metrics are described, although many other metrics are possible and may be included in claimed subject matter, such as other path gain/loss (PGL) metrics. In an embodiment, path gain loss metrics may comprise PGL0, PGL1, or PGL2. PGL0 corresponds to a general path gain-loss metric, referred to previously and discussed as PGL, for example. In contrast, PGL1 or PGL2 comprise path gain-loss metrics that may be employed to obtain a more detailed view of path gain-loss associated with one or more query recommendations, for example. In an example embodiment, to compute a PGL metric, such as PGL0, competitive search paths may be identified, such as previously described. For example, for an embodiment, at least two types of search paths may be identified: assisted search paths or non-assisted search paths. Time distributions may be compared for these two types of search paths to evaluate one or more query recommendations, for example. 
     In an embodiment, non-assisted search paths may be sorted by path time, for example. A path time at a 20th percentile level, for example, may be chosen as a pivotal path time in an embodiment. A 20 th  percentile level may imply that assisted search paths are to be faster than 80% of non-assisted search paths on average. However, claimed subject matter is, of course, not limited to any particular percentile level. A path time for an assisted search path may be compared against a pivotal threshold time, such as a pivotal path time, for non-assisted search paths on average, in one embodiment. If a path time of an assisted search path is shorter, in one embodiment, it may be counted as a gain point for a clicked or selected search suggestion. If a path time of an assisted search path is longer, in an embodiment, it may be counted as a loss point for a clicked or selected search suggestion. Likewise, gain or loss counters for search suggestions may be computed. A path gain or loss may be evaluated for a starting search query and an ending destination, as observed in a search session logs, for example. Gain or loss counts may be aggregated across clicked search suggestions to obtain gain or loss counts. Gain or loss counts may therefore indicate search suggestion performance in an embodiment. A PGL0 metric may be generated, for example, in accordance with the following relation:
 
 PGL 0=gain count/(gain count+loss count).
 
     Likewise, in an embodiment, path gain loss metrics may be computed for particular situations, such as by aggregating gain or loss counts across multiple search suggestions and computing a per-query metric, a per-category metric, etc. As mentioned, additional path gain-loss metrics, such as PGL1 or PGL2, may also be computed. For example, for an example embodiment, but without limitation, one metric, such as PGL1, may measure a utility of competing search suggestions. Another metric, such as PGL2, may measure performance of lateral search suggestions. 
     In an example embodiment, to compute a PGL1 metric, a set of competitive paths may be identified, as previously discussed, for example. However, for a metric of utility of competing search suggestions, such as PGL1, for example, assisted paths that do not have non-assisted path counterparts are omitted. A PGL1 metric may be generated using an approach similar to PGL0, such as:
 
 PGL 1=gain count/(gain count+loss count).
 
     A PGL1 metric may focus at least partially on search suggestions that have at least one competing non-assisted search path. Evaluations using a metric, such as PGL1, imply that in some instances competing search suggestions may reduce rather than increase efficiency or at least that using competing search suggestions may be less efficient than using lateral suggestions, on average. For example, PGL1 metric values may be lower than PGL2 metric values. 
     In an example embodiment, a metric may be employed for performance of lateral query recommendations, such as a PGL2 metric. A PGL2 metric may measure a performance of lateral suggestions. For lateral suggestions, search paths may be evaluated and gain or loss may be computed as follows, for example. A gain count may be increased if an assisted search path leads to a destination location. A loss count may be increased if an assisted search path is abandoned or otherwise does not lead to a destination location. By way of example, for an embodiment, as discussed, a dwell time corresponding to 100 seconds or longer may be employed to identify a destination location. A PGL2 metric may be generated in a manner similar to PGL0 and PGL1, as follows.
 
 PGL 2=gain count/(gain count+loss count).
 
     As indicated, metric values for lateral suggestions, such as PGL2, appear to be higher than metric values for competing suggestions, such as PGL1. It may be that a non-competing or lateral search suggestion may improve efficiency for a search query better than a competing search suggestion, therefore. For example, search assistance, such as providing query recommendations, in one or more embodiments, may be adjusted to offer more lateral search suggestions than competing search suggestions on a relative basis, although, of course claimed subject matter is not limited in scope in this respect. For example, a search suggestion generation process may be adjusted to produce 70% lateral search suggestions, for instance, instead of producing 45% lateral search suggestions. Of course, again, this is merely an illustrative example. Claimed subject matter is not limited in this respect, of course. 
     As another illustrative example, for an embodiment, search suggestions with relatively low metric values (e.g., PGL0&lt;0.3) may be omitted for a corresponding query search. Likewise, search suggestions with relatively higher metric values may be elevated above or promoted for use over search suggestions with relatively lower values. Generation of metrics or evaluation of search suggestions using metrics may be aggregated, as previously indicated, along a variety of categories, for example, on a per search suggestion basis, on a per query basis, etc. 
       FIG. 8  is a flow diagram  800  that illustrates an example method for generating a metric, such as in accordance with an embodiment. As illustrated, flow diagram  800  may include any of operational blocks  802 - 808 . Although operations  802 - 808  are shown and described in a particular order, it should be understood that methods within the scope of claimed subject may employ an alternative order or alternative operations. Likewise, for an embodiment, operations of flow diagram  800  may be performed so as to be fully or partially overlapping with each other or other operations not illustrated. In an embodiment, one or more of operations  802 - 808  may be performed at least partially by one or more computing platforms such as distributed system of servers, as one example. 
     At operation  802 , multiple competing search paths that start from a corresponding search query and terminate at a corresponding destination may be identified. At operation  804 , from multiple competing search paths, assisted search paths that include selection of one or more search suggestions may be identified. At operation  806 , from multiple competing search paths, non-assisted search paths that do not include a selection of a search suggestion may be identified. 
     At operation  808 , a metric may be generated based, at least in part, on comparisons between lengths of assisted search paths and lengths of non-assisted search paths. In an example embodiment, generation of a metric may further include sorting non-assisted search paths into a list based, at least in part, on lengths of non-assisted search paths to assess a of percentiles, for example. 
     In an example embodiment, a metric may comprise a path gain-loss metric. Generation of a metric may further include determining a path gain-loss metric at least partially by incrementing a gain count if a length of a particular assisted search path of identified assisted search paths is less than a threshold time, for example, or by increasing a loss count if the length of the particular assisted search path is greater than a threshold time, for example. Note also that in some embodiments these thresholds may not necessarily be the same. For example, a gain time threshold may be different than a loss time threshold. 
     For certain example implementations, a path gain loss metric, such as a PGL0 metric, a PGL1 metric, or a PGL2 metric, for example, may be calculated using session or search logs. Example implementations for generating embodiments of a path gain loss metric, for example, are described further herein below. However, claimed subject matter is not limited in these respects or to any particular metric or metrics. These are merely illustrative examples. 
     Procedures described herein may be implemented using a system of distributed computing platforms, as previously mentioned. By way of example but not limitation, procedures may be implemented using cloud or grid computing technology to handle large memory or computational demands, for example. A search path may be identified using, for example, a procedure as follows:
         1. For a search history found in one or more search logs:
           a. Query or click events may be sorted by timestamps. Results of timestamp sorting may include one or more raw search paths. A raw search path may comprise a path that includes several search sessions for related or unrelated search queries.   b. A raw path may be broken into shorter paths as follows:
               i. Period of inactivity among search events: A time interval between a search submission query and a preceding event in a raw path may be evaluated. If a time interval is greater than an inactivity threshold (e.g., five minutes), a latter query may be treated as a beginning of another search path. A search query submission after, e.g., five minutes of inactivity, be associated with different search intentions as compared to a preceding search query submission, although claimed subject matter is not limited in scope in this respect.   ii. Greater than a time threshold on a search result: A dwell time for a search result may be computed by subtracting a timestamp for the click from a timestamp of a subsequent event. If a search result click is found whose dwell time is greater than a dwell time threshold (e.g., that is larger than 100 seconds), the location may be treated as a destination location (or a last event) of a search path. Another search path starting from a subsequent search query submission may be started.   iii. For a final event in a raw path, there may be no subsequent event recorded in a search log. For final events, a dwell time of a final event is greater than a dwell time threshold.   
               c. Sub-paths produced via the above processing may be stored.   
           2. For search paths identified in 1 above, there may be at least two types of search paths: those with a destination or those without a destination
           a. For those search paths with a destination, paths may end at a search result click having its dwell time greater than a dwell time threshold (e.g., a page dwell time over 100 seconds). A last click may be deemed to comprise a destination.   b. For those search paths without a destination, paths may end on a final location having a dwell time less than a dwell time threshold.   
               

     In an example implementation, a path gain/loss (PGL) metric may be generated. For example, a baseline or general “PGL0” metric may be generated, such as using a procedure as follows, in an embodiment:
         1. Filter or remove search paths without a destination. Search paths with a destination may be handled as follows in an embodiment:   2. identify competitive search paths. To do so, identify combinations of a starting query and a destination from a collection of search paths. For an identified pair, e.g., &lt;starting query, destination&gt;, combination, retrieve paths with a corresponding starting query and destination. A collection of competitive search paths may be grouped together.   3. For a competitive path group identified in 2, classify search paths into at least two classes: assisted search paths or non-assisted search paths.
           If a search path includes a click or selection of a search suggestion, a corresponding search path may be termed an assisted search path.   If a search path does not include a click or selection of a search suggestion, a search path may be termed a non-assisted search path.   For non-assisted paths, sort search path by path time. A path time, for an embodiment, may be determined based, at least in part, on a timestamp difference of a destination and an initiating search query (e.g., path time=timestamp(destination)−timestamp(first query)). From sorted search paths, a path at a given percentile point, such as a 20th percentile point, may be identified. This path may be termed a pivotal path. A path time associated with a pivotal path may be termed a pivotal search time. A different percentile level for determining a pivotal path may be employed in alternate embodiments, of course. A smaller percentile level may imply a more improved efficiency for a search suggestion.   For an assisted search path, compare a path time versus a pivotal search time. If a path time of a given assisted path is smaller than a pivotal search time, credit one gain to a selected search suggestion on a given assisted search path. Otherwise, one loss may be debited to a the selected search suggestion. For a search suggestion for a particular initiating search query and destination, a gain counter or a loss counter may be maintained. For example, gain or loss counters may be implemented as follows:
               Gain(S,Q,U): A gain counter may track a gain count of a particular search suggestion S by evaluation of search paths that start from a corresponding query Q and end at a corresponding destination U.   Loss(S,Q,U): A loss counter may track a loss count of a particular suggestion S by evaluation of search paths that start from a corresponding query Q and end at a corresponding destination U.
                   For an assisted search path (e.g., paths that start from a corresponding query Q and end at a corresponding destination U)    If there are zero non-assisted paths with a corresponding initiating query Q and destination U, then    A pivotal search time may be set to be large (e.g., so large that other times in comparison are less to reflect that non-assisted search paths would take a long time to reach a corresponding destination.)    For a clicked or selected search suggestion (say, S) that appears on an assisted search path,    If a path time of an assisted path is smaller than (or equal to) a pivotal search time, then    Gain(S,Q,U) may be increased by one    Otherwise,    Loss(S,Q,U) may be increased by one.   
                   
               A list of updated gain or loss counters for multiple search suggestions that appear on assisted search paths may be produced.   
           4. Aggregate gain or loss counts for a search suggestion across available destinations given a corresponding initiating query. For example, compute a per-suggestion metric, such as PGL0, as follows:
           Given a list of gain or loss counts as computed in 3 above:   For a suggestion S and an initiating query Q, compute as follows:
               a aggregate gain counters across available destinations   
               
               

     
       
         
           
             
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                     aggregate loss counters across available destinations. 
                   
                 
               
             
           
         
       
    
     
       
         
           
             
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                     A resulting per-suggestion metric, such as PGL0, may be computed as follows: 
                   
                 
               
             
           
         
       
    
     
       
         
           
             
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                 Store or report computed PGL0(S,Q) values for multiple &lt;query,suggestion&gt; pairs. 
               
             
             5. Similarly, compute per-query PGL0 values by aggregating PGL values across multiple search suggestions. Specifically compute per-query PGL values as follows:
           Given a list of gain or loss counts as computed in 3 above:   A per-query PGL0 may be computed via aggregation:
               Aggregate gain counters across available destinations and search suggestions.   
               
         
           
         
       
    
     
       
         
           
             
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                     It may aggregate loss counters across available destinations and search suggestions. 
                   
                 
               
             
           
         
       
    
     
       
         
           
             
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                     A resulting per-query PGL0 may be computed as follows: 
                   
                 
               
             
           
         
       
    
     
       
         
           
             
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                 Provide computed metrics, such as PGL0(Q) values, for multiple queries. 
               
             
             6. To compute a per-category metric, PGL0, identify whether a search suggestion click is from a target category. Those suggestions clicked from a target category may participate in a per-category metric calculation. For example, a PGL0 value for a category, M, which is denoted as PGL0(M) herein below, may be computed. Operation 3 above may be revised for gain or loss counters as follows:
           Given a set of assisted search paths or non-assisted search paths as computed in 3 above:   For an assisted search path (e.g., that starts from a corresponding query Q and ends at a corresponding destination U):
               For a clicked or selected search suggestion (say, S) that appears on an assisted search path,
                   If a search suggestion click is not from category M, then skip the suggestion. A skipped suggestion may not contribute to gain or loss counts.   Similarly, compare a path time of an assisted search path versus a pivotal search time to update gain or loss counters:    a. Gain(S,Q,U,M)    b. Loss(S,Q,U,M)   
                   
               Given updated gain or loss counts for a search suggestion with respect to a target category, M, compute an per-metric, such as PGL0, as follows:
               A per-category gain may be computed:   
               
         
           
         
       
    
     
       
         
           
             
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                     Aggregate across available destinations, search suggestions, and search queries for a gain calculation 
                     An per-category loss may be computed: 
                   
                 
               
             
           
         
       
    
     
       
         
           
             
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                     A resulting per-category or category-level metric value, such as aPGL0 value, may be computed as follows: 
                   
                 
               
             
           
         
       
    
     
       
         
           
             
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     In an example implementation, a path gain/loss (PGL) metric may be generated. For example, a PGL1 metric that focuses at least partially on competitive search paths may be generated in an embodiment, using a procedure as follows:
         1. Operation 1 for PGL1 may mirror operation 1 above for PGL0.   2. Operation 2 for PGL1 may mirror operation 2 above for PGL0.   3. For a competitive path group identified as described above, classify its member search paths into at least two classes: assisted search paths or non-assisted search paths.
           To participate in a PGL1 calculation, competitive path groups having non-zero assisted search paths may be selected. For example, the following checks may be performed:
               Check if a number of assisted search paths is greater than zero:
                   If a number is zero, a corresponding competitive path group may be skipped and processing may be continued with a next competitive path group.   If a number is greater than zero, a pivotal search path or a pivotal search time may be computed as described above for a metric, such as PGL0. Corresponding groups of competitive paths may contribute to gain or loss counts.   
                   
               Other operations for determining a metric value, such as PGL1, may be analogous to those for another PGL metric, such as PGL0. A list of Gain(S,Q,U) or Loss(S,Q,U) counts as determined by evaluating competitive paths in search logs may be reported or stored.   
           4. Operations 4, 5, or 6 for per-suggestion, per-query, or per-category metrics, such as PGL1 calculations, respectively, may be implemented analogously to those operations described above for metric calculations, such as PGL0 calculations.       

     In an example implementation, a path gain/loss (PGL) metric may be generated. For example, a metric, such as PGL2, for example, that focuses at least partially on non-competitive assisted search paths may be generated. For an embodiment, a PGL2 metric may consider those assisted paths that may be skipped by a PGL1 metric. In contrast with certain examples for a PGL1 metric, a PGL2 metric may take into account search paths for search suggestions that do not reach a destination location. A PGL2 metric, such as for an embodiment, may be generated using, for example, a procedure as follows:
         1. Identify groups of competitive paths from search paths that reach a destination location.   2. For a competitive path group, classify member paths into at least two classes: assisted search paths or non-assisted search paths.
           A competitive path group may be skipped if at least one non-assisted search path exists.   Remaining assisted search paths may be reported or stored. For reported or stored assisted paths, there may be no corresponding non-assisted path to a corresponding destination.   
           3. For remaining assisted paths or search paths that do not reach a destination, evaluate clicked or selected search suggestions along a path that includes a dwell time for a final selection. Gain or loss counters may be updated as follows:
           For a search suggestion on a search path that starts from query Q and ends at a location U:
               If a dwell time at location U is smaller than a threshold (e.g., 100 seconds), then
                   A Loss(S,Q,U) counter may be increased by one.   
                   Otherwise, if a dwell time at location U is greater than or equal to a threshold (e.g., 100 seconds), then
                   A Gain(S,Q,U) counter may be increased by one.   
                   
               Gain or loss counts that are computed after evaluating search paths (e.g., including those without a destination) may be reported or stored.   
           4. Compute a per-suggestion metric, such as PGL2, by aggregating across destinations:
           Gain counters may be aggregated across destinations.   
               

     
       
         
           
             
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                 Loss counters may be aggregated across destinations. 
               
             
           
         
       
    
     
       
         
           
             
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                 A per-suggestion metric, such as PGL2, may be computed using: 
               
             
           
         
       
    
     
       
         
           
             
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             5. Compute a per-query PGL2 as follows:
           Gain counters may be aggregated across destinations and suggestions.   
         
           
         
       
    
     
       
         
           
             
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                 Loss counters may be aggregated across destinations and suggestions. 
               
             
           
         
       
    
     
       
         
           
             
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                       u 
                     
                     ) 
                   
                 
               
             
           
         
       
         
         
           
             
               
                 A per-query metric, such as PGL2, may be computed using: 
               
             
           
         
       
    
     
       
         
           
             
               PGL 
               ⁢ 
               
                   
               
               ⁢ 
               2 
               ⁢ 
               
                 ( 
                 Q 
                 ) 
               
             
             = 
             
               
                 Gain 
                 ⁡ 
                 
                   ( 
                   Q 
                   ) 
                 
               
               
                 
                   Gain 
                   ⁡ 
                   
                     ( 
                     Q 
                     ) 
                   
                 
                 + 
                 
                   Loss 
                   ⁡ 
                   
                     ( 
                     Q 
                     ) 
                   
                 
               
             
           
         
       
         
         
           
             6. Compute a per-category metric, such as PGL2, by filtering out those search suggestion clicks that are not associated with a target category M. An aggregating process may be performed analogously to that for a metric PGL0 calculation, such as in operation 6 as described above.
           Suggestions clicked that are irrelevant to a target category M may be filtered out:
               For remaining search suggestions clicked, Gain(S,Q,U,M) counters or Loss(S,Q,U,M) counters may be computed as follows:   
               Gain may be computed for a given category M with:   
         
           
         
       
    
     
       
         
           
             
               Gain 
               ⁡ 
               
                 ( 
                 M 
                 ) 
               
             
             = 
             
               
                 ∑ 
                 s 
                 
                     
                 
               
               ⁢ 
               
                 
                   ∑ 
                   q 
                   
                       
                   
                 
                 ⁢ 
                 
                   
                     ∑ 
                     u 
                     
                         
                     
                   
                   ⁢ 
                   
                     
                       Gain 
                       ⁡ 
                       
                         ( 
                         
                           s 
                           , 
                           q 
                           , 
                           u 
                           , 
                           M 
                         
                         ) 
                       
                     
                     . 
                   
                 
               
             
           
         
       
         
         
           
             
               
                 Loss may be computed for a given category M with: 
               
             
           
         
       
    
     
       
         
           
             
               Loss 
               ⁡ 
               
                 ( 
                 M 
                 ) 
               
             
             = 
             
               
                 ∑ 
                 s 
                 
                     
                 
               
               ⁢ 
               
                 
                   ∑ 
                   q 
                   
                       
                   
                 
                 ⁢ 
                 
                   
                     ∑ 
                     u 
                     
                         
                     
                   
                   ⁢ 
                   
                     
                       Loss 
                       ⁡ 
                       
                         ( 
                         
                           s 
                           , 
                           q 
                           , 
                           u 
                           , 
                           M 
                         
                         ) 
                       
                     
                     . 
                   
                 
               
             
           
         
       
         
         
           
             
               
                 A per-module PGL2 metric may be computed using: 
               
             
           
         
       
    
     
       
         
           
             
               PGL 
               ⁢ 
               
                   
               
               ⁢ 
               2 
               ⁢ 
               
                 ( 
                 M 
                 ) 
               
             
             = 
             
               
                 
                   Gain 
                   ⁡ 
                   
                     ( 
                     M 
                     ) 
                   
                 
                 
                   
                     Gain 
                     ⁡ 
                     
                       ( 
                       M 
                       ) 
                     
                   
                   + 
                   
                     Loss 
                     ⁡ 
                     
                       ( 
                       M 
                       ) 
                     
                   
                 
               
               . 
             
           
         
       
     
       FIG. 9  is a schematic block diagram  900  of example devices, according to an embodiment, that may realize at least one computing platform to implement one or more aspects of search suggestions that are described herein. As illustrated, block diagram  900  may include a first device  902   a  or a second device  902   b , which may be operatively coupled together via one or more networks  904 . A device  902  may comprise, correspond to, implement, or realize at least part of search suggestion resources  402 , user resources  406  (e.g., both of  FIG. 4 ), or a combination thereof, etc. Network  904  may correspond to communications network  404  (e.g., of  FIG. 4 ). 
     For certain example embodiments, first device  902   a  may be adapted at least to receive entered search terms or selections of user interface links from a user or to provide search results, search suggestions, or web documents to a user. Network  904 , as shown in  FIG. 9 , may be representative of one or more communication links, processes, or resources capable of supporting an exchange of signals between first device  902   a  and second device  902   b . Second device  902   b  may be adapted at least to generate search suggestions or a metric indicative of a characteristic of a search suggestion. 
     As illustrated, but by way of example only, second device  902   b  may include at least one communication interface  908 , one or more processors  910 , at least one interconnection  912 , or at least one memory  914 . Memory  914  may include at least a primary memory  914 ( 1 ) or a secondary memory  914 ( 2 ). Second device  902   b  may have access to at least one computer-readable medium  906 . Although not explicitly shown, first device  902   a  may also include any components illustrated with regard to second device  902   b.    
     For an example embodiment, but not by way of limitation, second device  902   b  may include at least one processor  910  that is operatively coupled to memory  914  via interconnection  912 . Memory  914  may comprise any data storage mechanism. Although not explicitly shown in  FIG. 9 , memory  914  may store or include instructions. Instructions stored in memory  914  may be executable by processor  910  to perform, for example, at least a portion of one or more procedures, methods, or any combination thereof, etc. that are described herein. Although illustrated in this example as being separate from processor  910 , it should be understood that at least a part of memory  914  may be provided within or otherwise co-located with or coupled directly to processor  910 . 
     As shown, second device  902   b  may be coupled to or have access to a computer-readable medium  906 . A computer-readable medium may include, for example, any medium that can store, carry, or make accessible data, code, or instructions for execution by one or more devices in block diagram  900 . Additionally or alternatively, a computer-readable medium  906  may comprise at least a portion of memory  914 . 
     Second device  902   b  may also include, for example, a communication interface  908  that may provide for or otherwise support an operative coupling of second device  902   b  to at least network  904 . By way of example but not limitation, communication interface  908  may include a network interface device or card, a modem, a router, a switch, a transceiver, or any combinations thereof, etc., just to name a few examples. Electrical digital signal(s) (not shown) may be manipulated by second device  902   b . By way of example but not limitation, electrical digital signals may be received from or transmitted onto network  904  using communication interface  908 . Additionally or alternatively, electrical digital signals may be stored to or read from memory  914  using interconnection  912 . 
     According to embodiments that include at least one memory, one or more portions of memory  914  may store signals representative of data or information as expressed by a particular state of memory  914 . For example, an electronic digital signal representative of data or information may be “stored” in a portion of a memory device by affecting or changing a state of such portions of memory  914  to represent data or information as binary information (e.g., as ones and zeros). As such, in a particular implementation, a change of state of a portion of memory to store a digital signal representative of data or information may constitute a transformation of memory  914  to a different state or thing. 
     In some circumstances, operation of a memory device, such as a change in state from a binary one to a binary zero or vice-versa, for example, may comprise a transformation, such as a physical transformation. With particular types of memory devices, such a physical transformation may comprise a physical transformation of an article to a different state or thing. By way of example but not limitation, for some types of memory devices, a change in state may involve an accumulation and storage of charge or a release of stored charge. Likewise, in other memory devices, a change of state may comprise a physical change or transformation in magnetic orientation or a physical change or transformation in molecular structure, such as from crystalline to amorphous or vice-versa. The foregoing is not intended to be an exhaustive list of all examples in which a change in state for a binary one to a binary zero or vice-versa in a memory device may comprise a transformation, such as a physical transformation. Rather, the foregoing description is intended to provide illustrative examples. 
     A storage medium may be non-transitory or comprise a non-transitory device. In this context, a non-transitory storage medium may include a device that is tangible, meaning that the device has a concrete physical form, although the device may change its physical state. Thus, for example, non-transitory may refer to a device that remains tangible despite a change in state. 
     It will, of course, also be understood that, although particular embodiments have been described, claimed subject matter is not limited in scope to a particular embodiment or implementation. For example, one embodiment may be in hardware, such as implemented with a device or combination of devices, as previously described, for example. Likewise, although claimed subject matter is not limited in scope in this respect, an embodiment may comprise one or more articles of manufacture, such as a storage medium or storage media, for example, that may have stored thereon instructions executable by a specific or special purpose system or apparatus. As one potential example, a specific or special purpose computing platform may include one or more processing units or processors; one or more input/output devices, such as a display, a keyboard or a mouse; one or more memories, such as static random access memory, dynamic random access memory, flash memory, or a hard drive; or any combination thereof; etc. Although, again, claimed subject matter is not limited in scope to this example. 
     Some portions of the detailed description included herein are presented in terms of algorithms or symbolic representations of operations on binary digital signals stored within a memory of a specific apparatus or special purpose computing device or platform. In the context of this particular specification, the term specific apparatus or the like may include a general purpose computer once it is programmed to perform particular operations pursuant to instructions from program software. Algorithmic descriptions or symbolic representations are examples of techniques used by those of ordinary skill in the signal processing or related arts to convey the substance of their work to others skilled in the art. An algorithm is here, and generally, considered to be a self-consistent sequence of operations or similar signal processing leading to a desired result. In this context, operations or processing involve physical manipulation of physical quantities. Typically, although not necessarily, such quantities may take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared or otherwise manipulated. It has proven convenient at times, principally for reasons of common usage, to refer to such signals as bits, data, values, elements, symbols, characters, terms, numbers, numerals, or the like. It should be understood, however, that these or similar terms are to be associated with appropriate physical quantities and are merely convenient labels. Unless specifically stated otherwise, as apparent from the discussion herein, it is appreciated that throughout this specification discussions utilizing terms such as “processing,” “computing,” “calculating,” “determining,” “generating,” “evaluating,” “obtaining,” “ascertaining,” “comparing,” “transmitting,” “receiving,” “identifying,” “providing,” “initiating transmission,” or the like refer to actions or processes of a specific apparatus, such as a special purpose computer or a similar special purpose electronic computing device. In the context of this specification, therefore, a special purpose computer or a similar special purpose electronic computing device is capable of manipulating or transforming signals, typically represented as physical electronic or magnetic quantities within memories, registers, or other information storage devices, transmission devices, or display devices of the special purpose computer or similar special purpose electronic computing device. 
     Reference throughout this specification to “one embodiment” or “an embodiment” may mean that a particular feature, structure, or characteristic described in connection with a particular embodiment may be included in at least one embodiment of claimed subject matter. Thus, appearances of the phrase “in one embodiment” or “an example embodiment” in various places throughout this specification are not necessarily intended to refer to the same embodiment or to any one particular embodiment described. Furthermore, it is to be understood that particular features, structures, or characteristics described may be combined in various ways in one or more embodiments. In general, of course, these and other issues may vary with the particular context of usage. Therefore, the particular context of the description or the usage of these terms may provide helpful guidance regarding inferences to be drawn for that context. 
     Likewise, the terms, “and” and “or” as used herein may include a variety of meanings that also is expected to depend at least in part upon the context in which such terms are used. Typically, “or” if used to associate a list, such as A, B or C, is intended to mean A, B, and C, here used in the inclusive sense, as well as A, B or C, here used in the exclusive sense. In addition, the term “one or more” as used herein may be used to describe any feature, structure, or characteristic in the singular or may be used to describe some combination of features, structures or characteristics. Though, it should be noted that this is merely an illustrative example and claimed subject matter is not limited to this example. 
     In the preceding description, various aspects of claimed subject matter have been described. For purposes of explanation, systems or configurations were set forth to provide an understanding of claimed subject matter. However, claimed subject matter may be practiced without those specific details. In other instances, well-known features were omitted or simplified so as not to obscure claimed subject matter. While certain features have been illustrated or described herein, many modifications, substitutions, changes, or equivalents will now occur to those skilled in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications or changes as fall within the true spirit of claimed subject matter.