Abstract:
A customizable ranking model of a search engine using custom ranking model configuration and parameters of a pre-defined human-readable format. The architecture can employ a markup language schema to represent the custom ranking model. In one implementation, the schema developed utilizes XML (extensible markup language) for representing the custom ranking model. Weights for dynamic and static relevance ingredients can be altered per ranking model and new relevance ingredients can be added. Additionally, features are provided for improving relevance such as adding terms to a thesaurus for synonym expansion, for example, the ability to deal with single terms either as compounds, and/or using custom word breaking rules.

Description:
BACKGROUND 
       [0001]    Typically, a search engine utilizes a ranking function to predict the degree of relevance of a document to a particular query. The ranking function takes multiple features from the document as inputs and computes a number that allows the search engine to sort the documents by predicted relevance. The ranking function (including its parameters) may be built into the search engine, or the search engine may allow the specification of multiple custom ranking functions. However, extensive and sophisticated customization of ranking models by the average administrator is non-existent. 
       SUMMARY 
       [0002]    The following presents a simplified summary in order to provide a basic understanding of some novel embodiments described herein. This summary is not an extensive overview, and it is not intended to identify key/critical elements or to delineate the scope thereof. Its sole purpose is to present some concepts in a simplified form as a prelude to the more detailed description that is presented later. 
         [0003]    The disclosed architecture supports customization of a ranking model of a search engine using custom ranking model configuration and parameters of a pre-defined format. The architecture employs a markup language schema to represent the custom ranking model. In one implementation, the schema developed utilizes XML (extensible markup language) for representing the custom ranking model. However, other equivalent representations can be employed. 
         [0004]    More specifically, administrators are now provided with the capability to tune relevance by enabling the creation of multiple ranking models that can be tuned for specific languages, verticals, and/or site experiences. Moreover, two models can allow an administrator to custom tune another model with reference to a baseline, for example. The weights for dynamic and static relevance ingredients can be altered per ranking model and new relevance ingredients can be added. Additionally, some aspects of the custom model can be exposed to administrators outside the model. For example, authoritative sites may need to be identified (along with site importance) as well as deprecated sites. Features are provided for improving relevance such as adding terms to a thesaurus for synonym expansion, for example, the ability to deal with single terms either as compounds, and/or using custom word breaking rules. These and other features can be true across all models, or localized. 
         [0005]    To the accomplishment of the foregoing and related ends, certain illustrative aspects are described herein in connection with the following description and the annexed drawings. These aspects are indicative of the various ways in which the principles disclosed herein can be practiced and all aspects and equivalents thereof are intended to be within the scope of the claimed subject matter. Other advantages and novel features will become apparent from the following detailed description when considered in conjunction with the drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]      FIG. 1  illustrates computer-implemented ranking model system in accordance with the disclosed architecture. 
           [0007]      FIG. 2  illustrates a simplified diagram of the features and elements of the schema for the custom ranking model. 
           [0008]      FIG. 3  illustrates a computer-implemented ranking model method in accordance with the disclosed architecture. 
           [0009]      FIG. 4  illustrates additional aspects of the method of  FIG. 3 . 
           [0010]      FIG. 5  illustrates a block diagram of a computing system for processing a customizable ranking function represented in a markup language in accordance with the disclosed architecture. 
       
    
    
     DETAILED DESCRIPTION 
       [0011]    A single ranking model means that all customizations to the model affect the search experience across the whole corpus. In the case of multilingual corpora or corpora that contain content for different audiences or even specialized search application, for example, search across customer data, new relevance ingredients or weighting existing relevance ingredients differently needs to be considered. 
         [0012]    Creating separate ranking models and enabling the separate ranking models to be applied to a subset of the content in a corpus provides administrators a lower risk way to evaluate the changes made to relevance. 
         [0013]    Moreover, picking selected language features such as improved handling of compounds and breaking rules provides a significant impact. This is applies particularly in Germany and Japan markets, for example, where specific search relevance issues can occur. 
         [0014]    The disclosed architecture provides relevance tuning capabilities by way of a clearly defined schema. In one implementation, described in detail herein, the schema for custom ranking model is represented in XML (extensible markup language). However, other equivalent representations can be employed. 
         [0015]    Reference is now made to the drawings, wherein like reference numerals are used to refer to like elements throughout. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding thereof. It may be evident, however, that the novel embodiments can be practiced without these specific details. In other instances, well known structures and devices are shown in block diagram form in order to facilitate a description thereof. The intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the claimed subject matter. 
         [0016]      FIG. 1  illustrates computer-implemented ranking model system  100  in accordance with the disclosed architecture. The system  100  can include a customizable ranking model  102  for ranking documents  104  resulting from a search, and a schema  106  that represents the customizable ranking model  102  in a schema written in a human-readable code  108  (e.g., a markup language). The human-readable code  108  can be extensible markup language (XML). The schema  106  facilitates application of a ranking function (e.g., BM25F) that manages query terms associated with multiple streams of data. 
         [0017]    The schema can represent query dependent ranking features and query independent ranking features. The schema can also represent a ranking model element that includes parameters for at least one of a static feature, a static feature for a small number of enumerable values, or query language matching. The schema can represent a ranking model element that includes a list of weightings for possible values of a feature, and ranking model elements that describe at least one of a rational transform type and associated parameters or inverse rational transform type and associated parameters. The schema can also represent ranking model elements that describe at least one of a linear transform and associated parameters or a logarithmic transform and associated parameters. These are just a few examples of the features that can be represented. Other features and elements can be utilized as desired in support of the customizable ranking model  102 . 
         [0018]      FIG. 2  illustrates a simplified diagram of the features and elements of the schema  200  for the custom ranking model. The schema  200  includes a root level ranking model element  202 . The ranking model element  202  has two child elements: a query dependent features element  204  and a query independent features element  206 . The query dependent features element  204  has a child query dependent feature element  208 . The query independent features element  206  has three child elements: a category feature element  210 , a query independent feature element  212  and a language feature element  214 . The category feature element  210  further has a child category element  216 . The query independent feature element  212  has a child transform element  218  for providing four transforms: a rational transform (transformRational), an inverse rational transform (transformInvRational), a linear transform (transformLinear), and a logarithmic transform (transformLogarithmic). Note that the schema  200  described herein is just one example markup language schema. Alternatively, other representations can be utilized as desired. Moreover, other elements and features can be utilized as well. 
         [0019]    Each of these elements and features will now be described in detail. The following description is one example of a schema that can be employed in custom ranking model search engines. This exemplary representation uses the XML (extensible markup language) in the schema. 
         [0020]    The XML namespace of each element in custom ranking model can be “http://schemas.company.com/office/20xx/rankingModel”. Attributes are all unqualified (no namespace). 
         [0021]    The rankingModel element is a root element of the custom ranking model. 
         [0000]    
       
         
               
               
               
               
             
               
               
               
             
           
               
                   
                   
               
             
             
               
                   
                 Attribute 
                 Mandatory 
                 Meaning 
               
               
                   
                   
               
               
                   
                 id 
                 required 
                 Unique model id - globally unique id (GUID) 
               
               
                   
                 name 
                 optional 
                 Name of the model - any descriptive string 
               
               
                   
                 description 
                 optional 
                 Description of the model - any descriptive string 
               
               
                   
                   
               
             
          
           
               
                 Child Element 
                 Cardinality 
                 Meaning 
               
               
                   
               
               
                 queryDependentFeatures 
                 1 
                 Parameters for BM25F feature; each 
               
               
                   
                   
                 queryDependentFeature (aka 
               
               
                   
                   
                 property) defined within this element 
               
               
                   
                   
                 is used for recall, that is the 
               
               
                   
                   
                 document matches query term when 
               
               
                   
                   
                 term can be found in at least one property. 
               
               
                 queryIndependentFeatures 
                 0 . . . 1 
                 Query independent features with 
               
               
                   
                   
                 parameters. 
               
               
                   
               
             
          
         
       
     
         [0022]    The queryDependentFeatures element defines one BM25F stream feature. Each element under queryIndependentFeatures defines one query independent ranking feature. 
         [0023]    A child element to the rankingModel element is queryDependentFeature with the following attributes. 
         [0000]    
       
         
               
               
               
             
           
               
                   
               
             
             
               
                 Child Element 
                 Cardinality 
                 Meaning 
               
               
                   
               
               
                 queryDependentFeature 
                 1 . . . * 
                 Textual property participating in 
               
               
                   
                   
                 BM25 
               
               
                   
               
               
                 Attribute 
                 Mandatory 
                 Meaning 
               
               
                   
               
               
                 pid 
                 required 
                 Managed property id 
               
               
                 name 
                 optional 
                 Name of property - any string 
               
               
                 weight 
                 required 
                 Parameter w 
               
               
                 lengthNormalization 
                 required 
                 Parameter b 
               
               
                   
               
             
          
         
       
     
         [0024]    BM25F is computed with the following formula: 
         [0000]    
       
         
           
             ScoreAdd 
             = 
             
               ( 
               
                 
                   ∑ 
                   
                     t 
                      
                     
                         
                     
                      
                     ε 
                      
                     
                         
                     
                      
                     Q 
                   
                   
                       
                   
                 
                  
                 
                     
                 
                  
                 
                   
                     
                       TF 
                       t 
                       ′ 
                     
                     
                       1 
                       + 
                       
                         TF 
                         t 
                         ′ 
                       
                     
                   
                   · 
                   
                     log 
                      
                     
                       ( 
                       
                         N 
                         
                           n 
                           t 
                         
                       
                       ) 
                     
                   
                 
               
               ) 
             
           
         
       
       
         
           
             
               TF 
               t 
               ′ 
             
             = 
             
               ( 
               
                 
                   ∑ 
                   
                     p 
                      
                     
                         
                     
                      
                     ε 
                      
                     
                         
                     
                      
                     D 
                   
                   
                       
                   
                 
                  
                 
                     
                 
                  
                 
                   
                     TF 
                     
                       t 
                       , 
                       p 
                     
                   
                   · 
                   
                     w 
                     p 
                   
                   · 
                   
                     
                       1 
                       + 
                       
                         b 
                         p 
                       
                     
                     
                       ( 
                       
                         
                           
                             DL 
                             p 
                           
                           
                             AVDL 
                             p 
                           
                         
                         + 
                         
                           b 
                           p 
                         
                       
                       ) 
                     
                   
                 
               
               ) 
             
           
         
       
     
         [0000]    where Q is a query, D is a document, t is a query term, p is a property (queryDependentFeature) of the document, TF t,p  is the term frequency=number of times the term t appears in the property p of the document, DL p  is the length of the property p (number of terms), AVDL p  is the average length of the property in the collection, N (uppercase) is the number of documents in the corpus, n t  is the number of documents containing the given query term t, and, w p  and b p  are parameters (w p  is the importance or weight of that stream or field, and b p  is the importance of length normalization). 
         [0025]    The overall schema for score computation for any feature is as follows. The score of the document is computed according to the following formula: 
         [0000]    
       
         
           
             Score 
             = 
             
               
                 ∑ 
                 F 
                 
                     
                 
               
                
               
                   
               
                
               
                 ScoreAdd 
                  
                 
                   ( 
                   F 
                   ) 
                 
               
             
           
         
       
     
         [0000]    where ScoreAdd is a function of any feature described herein, and F is each ranking feature defined in the model. 
         [0026]    A child element to the rankingModel element is queryIndependentFeature with the following attributes and list of query independent ranking features. Children can occur in any order. At least one child is presented if the queryIndependentFeatures element is presented. 
         [0000]    
       
         
               
               
               
             
           
               
                   
               
               
                 Child Element 
                 Cardinality 
                 Meaning 
               
               
                   
               
             
             
               
                 categoryFeature 
                 0 . . . * 
                 Parameters for static feature 
               
               
                   
                   
                 with small number of 
               
               
                   
                   
                 enumerable integer values 
               
               
                   
                   
                 (feature like FileType) 
               
               
                 queryIndependentFeature 
                 0 . . . * 
                 Parameters for static feature. 
               
               
                 languageFeature 
                 0 . . . * 
                 Parameters for a case of 
               
               
                   
                   
                 categoryFeature - query 
               
               
                   
                   
                 language matching. 
               
               
                   
               
             
          
         
       
     
         [0027]    A child element of the queryIndependentFeatures element is the categoryFeature element, defined with the following attributes and child element. 
         [0000]    
       
         
               
               
               
               
             
               
               
               
             
           
               
                   
                   
               
             
             
               
                   
                 Attribute 
                 Mandatory 
                 Meaning 
               
               
                   
                   
               
               
                   
                 pid 
                 required 
                 Managed property id, defining static 
               
               
                   
                   
                   
                 storage where raw feature value is 
               
               
                   
                   
                   
                 taken from. 
               
               
                   
                 default 
                 required 
                 Default value (category) used when 
               
               
                   
                   
                   
                 storage is not available. 
               
               
                   
                 name 
                 optional 
                 Name of feature - any string 
               
               
                   
                   
               
             
          
           
               
                 Child Element 
                 Cardinality 
                 Meaning 
               
               
                   
               
               
                 Category 
                 1 . . . * 
                 List with score additions for each 
               
               
                   
                   
                 possible value (integer) of the feature. 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
           
             
               ScoreAdd 
                
               
                 ( 
                 x 
                 ) 
               
             
             = 
             
               number 
                
               
                   
               
                
               specified 
                
               
                   
               
                
               in 
                
               
                 
                   category 
                    
                   
                     [ 
                     
                       
                         @ 
                         value 
                       
                       = 
                       x 
                     
                     ] 
                   
                 
                 
                   @ 
                   weight 
                 
               
                
               attribute 
             
           
         
       
     
         [0028]    The category element is a child element to the categoryFeatures element and can include the following attributes. 
         [0000]    
       
         
               
               
               
               
             
           
               
                   
                   
               
               
                   
                 Attribute 
                 Mandatory 
                 Meaning 
               
               
                   
                   
               
             
             
               
                   
                 value 
                 required 
                 Raw feature value that defines this 
               
               
                   
                   
                   
                 category 
               
               
                   
                 name 
                 optional 
                 Name of category - any string 
               
               
                   
                 weight 
                 required 
                 Weight = score addition for this 
               
               
                   
                   
                   
                 category 
               
               
                   
                   
               
             
          
         
       
     
         [0029]    The queryIndependentFeature element is a child element to the queryIndependentFeatures element, includes parameters for a static feature, and is defined with the following attributes. 
         [0000]    
       
         
               
               
               
               
             
               
               
               
             
           
               
                   
                   
               
             
             
               
                   
                 Attribute 
                 Mandatory 
                 Meaning 
               
               
                   
                   
               
               
                   
                 pid 
                 required 
                 Managed property id, defining 
               
               
                   
                   
                   
                 static storage where raw 
               
               
                   
                   
                   
                 feature value is taken from. 
               
               
                   
                 name 
                 optional 
                 Name of feature - any string 
               
               
                   
                 default 
                 required 
                 Default value used when 
               
               
                   
                   
                   
                 storage is not available. 
               
               
                   
                 weight 
                 required 
                 Weight of this feature 
               
               
                   
                   
               
             
          
           
               
                 Child Element 
                 Cardinality 
                 Meaning 
               
               
                   
               
               
                 transformRational, 
                 choice (one of) 
                 Type and parameters of 
               
               
                 transformInvRational, 
                   
                 transform function. 
               
               
                 transformLinear, 
               
               
                 transformLogarithmic 
               
               
                 precompute 
                 0 . . . 1 
                 Optimization parameters 
               
               
                   
               
             
          
         
       
     
         [0000]      ScoreAdd( x )=Transform( x )· W  
 
         [0000]    where Transform is a transform function specified in the child element, and W is the weight. Note that the four transforms listed above are examples, in that other transforms can be employed as desired. 
         [0030]    The languageFeature element is a child element to the queryIndependentFeatures element, is a query language matching feature, and can include the following attributes. 
         [0000]    
       
         
               
               
               
               
             
           
               
                   
                   
               
               
                   
                 Attribute 
                 Mandatory 
                 Meaning 
               
               
                   
                   
               
             
             
               
                   
                 pid 
                 Required 
                 Managed property id, defining static 
               
               
                   
                   
                   
                 storage from where LCID is taken. 
               
               
                   
                 name 
                 Optional 
                 Name of feature - any string 
               
               
                   
                 default 
                 Required 
                 Default value used when storage is 
               
               
                   
                   
                   
                 not available; 0 or 1. 
               
               
                   
                 weight 
                 Required 
                 Weight of this feature 
               
               
                   
                   
               
             
          
         
       
     
         [0031]    The pid is a property id which contains an LCID, one per document. An LCID is the locale identifier, which is a number that represents a language/region/sort combination that can be associated with date, time, number, currency and other formatting, calendar preferences, input methods, sorting preferences, and more. The raw feature value is 1, if the primary language of the query is equal to the primary language of the stored LCID (except Chinese, where Chinese Simplified is considered different from Chinese Traditional) or LCID is neutral; otherwise, the raw feature value is 0. If no static storage is available for the specified pid, then the raw feature value is as specified in the default attribute. 
         [0000]      ScoreAdd( x )= x·W    
         [0000]    where W is the weight. 
         [0032]    The transformRational element is a child element to the queryIndependentFeature element, and includes the following attribute. 
         [0000]    
       
         
               
               
               
               
             
           
               
                   
                   
               
               
                   
                 Attribute 
                 Mandatory 
                 Meaning 
               
               
                   
                   
               
             
             
               
                   
                 k 
                 required 
                 Parameter 
               
               
                   
                   
               
             
          
         
       
     
         [0000]    
       
         
           
             
               Transform 
                
               
                 ( 
                 x 
                 ) 
               
             
             = 
             
               x 
               
                 k 
                 + 
                 x 
               
             
           
         
       
     
         [0033]    The transformInvRational element is a child element to the queryIndependentFeature element, and includes the following attribute. 
         [0000]    
       
         
               
               
               
               
             
           
               
                   
                   
               
               
                   
                 Attribute 
                 Mandatory 
                 Meaning 
               
               
                   
                   
               
             
             
               
                   
                 k 
                 required 
                 Parameter 
               
               
                   
                   
               
             
          
         
       
     
         [0000]    
       
         
           
             
               Transform 
                
               
                 ( 
                 x 
                 ) 
               
             
             = 
             
               1 
               
                 1 
                 + 
                 
                   k 
                   · 
                   x 
                 
               
             
           
         
       
     
         [0034]    The transformLinear element is a child element to the queryIndependentFeature element, and includes the following attribute. 
         [0000]    
       
         
               
               
               
               
             
           
               
                   
                   
               
               
                   
                 Attribute 
                 Mandatory 
                 Meaning 
               
               
                   
                   
               
             
             
               
                   
                 max 
                 required 
                 Upper bound 
               
               
                   
                   
               
             
          
         
       
     
         [0000]      Transform( x )=min( x ,max) 
         [0035]    The transformLogarithmic element is a child element to the queryIndependentFeature element, and includes the following attributes. 
         [0000]    
       
         
               
               
               
               
             
           
               
                   
                   
               
               
                   
                 Attribute 
                 Mandatory 
                 Meaning 
               
               
                   
                   
               
             
             
               
                   
                 b 
                 required 
                 Parameter 
               
               
                   
                 max 
                 required 
                 Upper bound 
               
               
                   
                   
               
             
          
         
       
     
         [0000]      Transform( x )=Log e (min( x ,max)+ b ) 
         [0036]    The precompute element is a child element to the queryIndependentFeature element, and includes the following attributes. This element, when present, instructs a ranker to pre-compute (optimize) computation of a transform function for the range of x argument from the “from” value, inclusive, to the “to” value, exclusive. 
         [0000]    
       
         
               
               
               
               
             
           
               
                   
                   
               
               
                   
                 Attribute 
                 Mandatory 
                 Meaning 
               
               
                   
                   
               
             
             
               
                   
                 from 
                 required 
                 Lower bound 
               
               
                   
                 to 
                 required 
                 Exclusive upper bound 
               
               
                   
                   
               
             
          
         
       
     
         [0037]    Following is an example of a relevance model XML schema in accordance with the disclosed architecture: 
         [0000]    
       
         
               
             
               
               
             
               
               
             
               
               
             
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
             
               
               
             
               
               
             
               
             
               
               
             
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
             
               
               
             
               
             
               
               
             
               
             
               
               
             
               
             
               
               
             
               
             
               
               
             
               
             
               
               
             
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
             
               
               
             
               
               
             
               
               
             
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
             
               
               
             
               
               
             
               
               
             
               
             
               
               
             
               
             
               
               
             
               
             
               
               
             
               
               
             
               
               
             
               
             
               
               
             
               
             
               
               
             
               
               
             
               
               
             
               
             
               
               
             
               
               
             
               
               
             
               
               
             
               
             
               
               
             
               
             
               
               
             
               
             
               
               
             
               
             
           
               
                   
               
             
             
               
                 &lt;?xml version=“1.0”?&gt; 
               
               
                 &lt;xs:schema attributeFormDefault=“unqualified” 
               
               
                 elementFormDefault=“qualified” 
               
               
                 targetNamespace=“http://schemas.company.com/office/20xx/rankingModel” 
               
               
                 xmlns:xs=“http://www.w3.org/2001/XMLSchema” 
               
               
                 xmlns:rm=“http://schemas.company.com/office/20xx/rankingModel”&gt; 
               
             
          
           
               
                   
                 &lt;xs:simpleType name=“GUIDType”&gt; 
               
             
          
           
               
                   
                 &lt;xs:restriction base=“xs:string”&gt; 
               
             
          
           
               
                   
                 &lt;xs:pattern value=“[A-Fa-f0-9]{8}−([A-Fa-f0-9]{4}−){3}[A- 
               
             
          
           
               
                 Fa-f0-9]{12}”/&gt; 
               
             
          
           
               
                   
                 &lt;/xs:restriction&gt; 
               
             
          
           
               
                   
                 &lt;/xs:simpleType&gt; 
               
               
                   
                 &lt;xs:simpleType name=“pidType”&gt; 
               
             
          
           
               
                   
                 &lt;xs:restriction base=“xs:unsignedShort”&gt; 
               
             
          
           
               
                   
                 &lt;xs:minInclusive value=“1”/&gt; 
               
             
          
           
               
                   
                 &lt;/xs:restriction&gt; 
               
             
          
           
               
                   
                 &lt;/xs:simpleType&gt; 
               
               
                   
                 &lt;xs:simpleType name=“weightType”&gt; 
               
             
          
           
               
                   
                 &lt;xs:restriction base=“xs:float”&gt; 
               
             
          
           
               
                   
                 &lt;xs:minInclusive value=“−1000000”/&gt; 
               
               
                   
                 &lt;xs:maxInclusive value=“1000000”/&gt; 
               
             
          
           
               
                   
                 &lt;/xs:restriction&gt; 
               
             
          
           
               
                   
                 &lt;/xs:simpleType&gt; 
               
               
                   
                 &lt;xs:simpleType name=“nonnegativeWeightType”&gt; 
               
             
          
           
               
                   
                 &lt;xs:restriction base=“xs:float”&gt; 
               
             
          
           
               
                   
                 &lt;xs:minInclusive value=“0”/&gt; 
               
               
                   
                 &lt;xs:maxInclusive value=“1000000”/&gt; 
               
             
          
           
               
                   
                 &lt;/xs:restriction&gt; 
               
             
          
           
               
                   
                 &lt;/xs:simpleType&gt; 
               
               
                   
                 &lt;xs:simpleType name=“lengthNormalizationType”&gt; 
               
             
          
           
               
                   
                 &lt;xs:restriction base=“xs:float”&gt; 
               
             
          
           
               
                   
                 &lt;xs:minInclusive value=“0”/&gt; 
               
               
                   
                 &lt;xs:maxInclusive value=“1000000”/&gt; 
               
             
          
           
               
                   
                 &lt;/xs:restriction&gt; 
               
             
          
           
               
                   
                 &lt;/xs:simpleType&gt; 
               
               
                   
                 &lt;xs:complexType name=“transformRationalType”&gt; 
               
             
          
           
               
                   
                 &lt;xs:attribute name=“k” use=“required”&gt; 
               
             
          
           
               
                   
                 &lt;xs:simpleType&gt; 
               
             
          
           
               
                   
                 &lt;xs:restriction base=“xs:float”&gt; 
               
             
          
           
               
                   
                 &lt;xs:minExclusive value=“0”/&gt; 
               
             
          
           
               
                   
                 &lt;/xs:restriction&gt; 
               
             
          
           
               
                   
                 &lt;/xs:simpleType&gt; 
               
             
          
           
               
                   
                 &lt;/xs:attribute&gt; 
               
             
          
           
               
                   
                 &lt;/xs:complexType&gt; 
               
               
                   
                 &lt;xs:complexType name=“transformInvRationalType”&gt; 
               
             
          
           
               
                   
                 &lt;xs:attribute name=“k” use=“required”&gt; 
               
             
          
           
               
                   
                 &lt;xs:simpleType&gt; 
               
             
          
           
               
                   
                 &lt;xs:restriction base=“xs:float”&gt; 
               
             
          
           
               
                   
                 &lt;xs:minExclusive value=“0”/&gt; 
               
               
                   
                 &lt;xs:maxInclusive value=“1000000”/&gt; 
               
             
          
           
               
                   
                 &lt;/xs:restriction&gt; 
               
             
          
           
               
                   
                 &lt;/xs:simpleType&gt; 
               
             
          
           
               
                   
                 &lt;/xs:attribute&gt; 
               
             
          
           
               
                   
                 &lt;/xs:complexType&gt; 
               
               
                   
                 &lt;xs:complexType name=“transformLinearType”&gt; 
               
             
          
           
               
                   
                 &lt;xs:attribute name=“max” type=“xs:unsignedInt” 
               
             
          
           
               
                 use=“required”/&gt; 
               
             
          
           
               
                   
                 &lt;/xs:complexType&gt; 
               
               
                   
                 &lt;xs:complexType name=“transformLogarithmicType”&gt; 
               
             
          
           
               
                   
                 &lt;xs:attribute name=“b” use=“required”&gt; 
               
             
          
           
               
                   
                 &lt;xs:simpleType&gt; 
               
             
          
           
               
                   
                 &lt;xs:restriction base=“xs:float”&gt; 
               
             
          
           
               
                   
                 &lt;xs:minExclusive value=“0”/&gt; 
               
               
                   
                 &lt;xs:maxInclusive value=“1000000”/&gt; 
               
             
          
           
               
                   
                 &lt;/xs:restriction&gt; 
               
             
          
           
               
                   
                 &lt;/xs:simpleType&gt; 
               
             
          
           
               
                   
                 &lt;/xs:attribute&gt; 
               
               
                   
                 &lt;xs:attribute name=“max” type=“xs:unsignedInt” 
               
             
          
           
               
                 use=“required”/&gt; 
               
             
          
           
               
                   
                 &lt;/xs:complexType&gt; 
               
               
                   
                 &lt;xs:complexType name=“precomputeType”&gt; 
               
             
          
           
               
                   
                 &lt;xs:attribute name=“from” type=“xs:unsignedInt” 
               
             
          
           
               
                 use=“required”/&gt; 
               
             
          
           
               
                   
                 &lt;xs:attribute name=“to” type=“xs:unsignedInt” 
               
             
          
           
               
                 use=“required”/&gt; 
               
             
          
           
               
                   
                 &lt;/xs:complexType&gt; 
               
               
                   
                 &lt;xs:complexType name=“queryIndependentFeatureType”&gt; 
               
             
          
           
               
                   
                 &lt;xs:sequence&gt; 
               
             
          
           
               
                   
                 &lt;xs:choice&gt; 
               
             
          
           
               
                   
                 &lt;xs:element name=“transformRational” 
               
             
          
           
               
                 type=“rm:transformRationalType”/&gt; 
               
             
          
           
               
                   
                 &lt;xs:element name=“transformInvRational” 
               
             
          
           
               
                 type=“rm:transformInvRationalType”/&gt; 
               
             
          
           
               
                   
                 &lt;xs:element name=“transformLinear” 
               
             
          
           
               
                 type=“rm:transformLinearType”/&gt; 
               
             
          
           
               
                   
                 &lt;xs:element name=“transformLogarithmic” 
               
             
          
           
               
                 type=“rm:transformLogarithmicType”/&gt; 
               
             
          
           
               
                   
                 &lt;/xs:choice&gt; 
               
               
                   
                 &lt;xs:element minOccurs=“0” name=“precompute” 
               
             
          
           
               
                 type=“rm:precomputeType”/&gt; 
               
             
          
           
               
                   
                 &lt;/xs:sequence&gt; 
               
               
                   
                 &lt;xs:attribute name=“name” type=“xs:string” use=“optional” /&gt; 
               
               
                   
                 &lt;xs:attribute name=“pid” type=“rm:pidType” use=“required” /&gt; 
               
               
                   
                 &lt;xs:attribute name=“default” type=“xs:unsignedInt” 
               
             
          
           
               
                 use=“required” /&gt; 
               
             
          
           
               
                   
                 &lt;xs:attribute name=“weight” type=“rm:weightType” 
               
             
          
           
               
                 use=“required” /&gt; 
               
             
          
           
               
                   
                 &lt;/xs:complexType&gt; 
               
               
                   
                 &lt;xs:complexType name=“categoryFeatureType”&gt; 
               
             
          
           
               
                   
                 &lt;xs:sequence&gt; 
               
             
          
           
               
                   
                 &lt;xs:element maxOccurs=“unbounded” name=“category”&gt; 
               
             
          
           
               
                   
                 &lt;xs:complexType&gt; 
               
             
          
           
               
                   
                 &lt;xs:attribute name=“name” type=“xs:string” 
               
             
          
           
               
                 use=“optional” /&gt; 
               
             
          
           
               
                   
                 &lt;xs:attribute name=“value” use=“required”&gt; 
               
             
          
           
               
                   
                 &lt;xs:simpleType&gt; 
               
             
          
           
               
                   
                 &lt;xs:restriction base=“xs:unsignedInt”&gt; 
               
             
          
           
               
                   
                 &lt;xs:maxInclusive value=“1000000”/&gt; 
               
             
          
           
               
                   
                 &lt;/xs:restriction&gt; 
               
             
          
           
               
                   
                 &lt;/xs:simpleType&gt; 
               
             
          
           
               
                   
                 &lt;/xs:attribute&gt; 
               
               
                   
                 &lt;xs:attribute name=“weight” type=“rm:weightType” 
               
             
          
           
               
                 use=“required” /&gt; 
               
             
          
           
               
                   
                 &lt;/xs:complexType&gt; 
               
             
          
           
               
                   
                 &lt;/xs:element&gt; 
               
             
          
           
               
                   
                 &lt;/xs:sequence&gt; 
               
               
                   
                 &lt;xs:attribute name=“name” type=“xs:string” use=“optional” /&gt; 
               
               
                   
                 &lt;xs:attribute name=“pid” type=“rm:pidType” use=“required” /&gt; 
               
               
                   
                 &lt;xs:attribute name=“default” type=“xs:unsignedInt” 
               
             
          
           
               
                 use=“required” /&gt; 
               
             
          
           
               
                   
                 &lt;/xs:complexType&gt; 
               
               
                   
                 &lt;xs:complexType name=“languageFeatureType”&gt; 
               
             
          
           
               
                   
                 &lt;xs:attribute name=“name” type=“xs:string” use=“optional” /&gt; 
               
               
                   
                 &lt;xs:attribute name=“pid” type=“rm:pidType” use=“required” /&gt; 
               
               
                   
                 &lt;xs:attribute name=“default” use=“required”&gt; 
               
             
          
           
               
                   
                 &lt;xs:simpleType&gt; 
               
             
          
           
               
                   
                 &lt;xs:restriction base=“xs:unsignedByte”&gt; 
               
             
          
           
               
                   
                 &lt;xs:maxInclusive value=“1”/&gt; 
               
             
          
           
               
                   
                 &lt;/xs:restriction&gt; 
               
             
          
           
               
                   
                 &lt;/xs:simpleType&gt; 
               
             
          
           
               
                   
                 &lt;/xs:attribute&gt; 
               
               
                   
                 &lt;xs:attribute name=“weight” type=“rm:weightType” 
               
             
          
           
               
                 use=“required” /&gt; 
               
             
          
           
               
                   
                 &lt;/xs:complexType&gt; 
               
               
                   
                 &lt;xs:complexType name=“queryIndependentFeaturesType”&gt; 
               
             
          
           
               
                   
                 &lt;xs:choice minOccurs=“1” maxOccurs=“unbounded”&gt; 
               
             
          
           
               
                   
                 &lt;xs:element name=“queryIndependentFeature” 
               
             
          
           
               
                 type=“rm:queryIndependentFeatureType”/&gt; 
               
             
          
           
               
                   
                 &lt;xs:element name=“categoryFeature” 
               
             
          
           
               
                 type=“rm:categoryFeatureType”/&gt; 
               
             
          
           
               
                   
                 &lt;xs:element name=“languageFeature” 
               
             
          
           
               
                 type=“rm:languageFeatureType”/&gt; 
               
             
          
           
               
                   
                 &lt;/xs:choice&gt; 
               
             
          
           
               
                   
                 &lt;/xs:complexType&gt; 
               
               
                   
                 &lt;xs:complexType name=“queryDependentFeatureType”&gt; 
               
             
          
           
               
                   
                 &lt;xs:attribute name=“name” type=“xs:string” use=“optional” /&gt; 
               
               
                   
                 &lt;xs:attribute name=“pid” type=“rm:pidType” use=“required” /&gt; 
               
               
                   
                 &lt;xs:attribute name=“weight” type=“rm:nonnegativeWeightType” 
               
             
          
           
               
                 use=“required”/&gt; 
               
             
          
           
               
                   
                 &lt;xs:attribute name=“lengthNormalization” 
               
             
          
           
               
                 type=“rm:lengthNormalizationType” use=“required” /&gt; 
               
             
          
           
               
                   
                 &lt;/xs:complexType&gt; 
               
               
                   
                 &lt;xs:complexType name=“queryDependentFeaturesType”&gt; 
               
             
          
           
               
                   
                 &lt;xs:sequence&gt; 
               
             
          
           
               
                   
                 &lt;xs:element minOccurs=“1” maxOccurs=“unbounded” 
               
             
          
           
               
                 name=“queryDependentFeature” type=“rm:queryDependentFeatureType”/&gt; 
               
             
          
           
               
                   
                 &lt;/xs:sequence&gt; 
               
             
          
           
               
                   
                 &lt;/xs:complexType&gt; 
               
               
                   
                 &lt;xs:complexType name=“rankingModelType”&gt; 
               
             
          
           
               
                   
                 &lt;xs:all&gt; 
               
             
          
           
               
                   
                 &lt;xs:element name=“queryDependentFeatures” 
               
             
          
           
               
                 type=“rm:queryDependentFeaturesType”/&gt; 
               
             
          
           
               
                   
                 &lt;xs:element name=“queryIndependentFeatures” 
               
             
          
           
               
                 type=“rm:queryIndependentFeaturesType” minOccurs=“0”/&gt; 
               
             
          
           
               
                   
                 &lt;/xs:all&gt; 
               
               
                   
                 &lt;xs:attribute name=“id” type=“rm:GUIDType” use=“required” /&gt; 
               
               
                   
                 &lt;xs:attribute name=“name” type=“xs:string” use=“optional” /&gt; 
               
               
                   
                 &lt;xs:attribute name=“description” type=“xs:string” 
               
             
          
           
               
                 use=“optional” /&gt; 
               
             
          
           
               
                   
                 &lt;/xs:complexType&gt; 
               
               
                   
                 &lt;xs:element name=“rankingModel” type=“rm:rankingModelType”/&gt; 
               
             
          
           
               
                 &lt;/xs:schema&gt; 
               
               
                   
               
             
          
         
       
     
         [0038]    Put another way, disclosed is computer-implemented ranking model system that comprises a customizable ranking model that employs a text ranking formula for processing multiple text fields, and a schema that represents elements of the customizable ranking model in XML. Some of the text fields can be defined out-of-the box and other fields can be introduced like other elements. The text ranking formula is a BM25F ranking function. The schema represents query dependent ranking features and query independent ranking features. The schema represents a query independent ranking feature that includes parameters for at least one of a static feature or a static feature for a small number of enumerable values, and a query dependent ranking feature that includes parameters for query language matching. The schema represents a ranking model element that includes a list of weightings for possible values of a feature. The schema represents a ranking model element that employs an arbitrary transform and associated parameters, where the arbitrary transform and associated parameters are one of a rational transform, an inverse rational transform, a linear transform, and a logarithmic transform. 
         [0039]    Note that as described above, the language feature element  214  of  FIG. 2  is illustrated in association with query independent features. This is only one example of a model schema, however. A query dependent feature is any field that can be used as a stream for BM25F; in other words, any feature that requires matching on the query terms entered by the user. There is other information from the user query, including context, such as language, that can be used as ranking, and is query dependent. However, in situations where a user employs the same language for all queries, the language feature can also operate as query independent. In other words, the language feature can depend on the query. However, this is not a requirement as the language feature can look at an unchanging stored value. Thus, the language feature can be query dependent, query independent, or dependent on some other variable. In a broader sense, this can be true for any query independent features. 
         [0040]    Included herein is a set of flow charts representative of exemplary methodologies for performing novel aspects of the disclosed architecture. While, for purposes of simplicity of explanation, the one or more methodologies shown herein, for example, in the form of a flow chart or flow diagram, are shown and described as a series of acts, it is to be understood and appreciated that the methodologies are not limited by the order of acts, as some acts may, in accordance therewith, occur in a different order and/or concurrently with other acts from that shown and described herein. For example, those skilled in the art will understand and appreciate that a methodology could alternatively be represented as a series of interrelated states or events, such as in a state diagram. Moreover, not all acts illustrated in a methodology may be required for a novel implementation. 
         [0041]      FIG. 3  illustrates a computer-implemented ranking model method in accordance with the disclosed architecture. At  300 , a schema of configuration information and parameters is defined for a customizable ranking model according to a markup language. At  302 , the customizable ranking model is configured according to the schema. 
         [0042]      FIG. 4  illustrates additional aspects of the method of  FIG. 3 . At  400 , query dependent ranking features and query independent ranking features are defined in the schema. At  402 , a text ranking function is defined for processing multiple text fields. At  404 , weighting values are applied to one or more of features of the customizable ranking model. At  406 , rational and linear transforms are configured for a query independent ranking feature. 
         [0043]    As used in this application, the terms “component” and “system” are intended to refer to a computer-related entity, either hardware, a combination of hardware and software, software, or software in execution. For example, a component can be, but is not limited to being, a process running on a processor, a processor, a hard disk drive, multiple storage drives (of optical, solid state, and/or magnetic storage medium), an object, an executable, a thread of execution, a program, and/or a computer. By way of illustration, both an application running on a server and the server can be a component. One or more components can reside within a process and/or thread of execution, and a component can be localized on one computer and/or distributed between two or more computers. The word “exemplary” may be used herein to mean serving as an example, instance, or illustration. Any aspect or design described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects or designs. 
         [0044]    Referring now to  FIG. 5 , there is illustrated a block diagram of a computing system  500  for processing a customizable ranking function represented in a markup language in accordance with the disclosed architecture. In order to provide additional context for various aspects thereof,  FIG. 5  and the following description are intended to provide a brief, general description of the suitable computing system  500  in which the various aspects can be implemented. While the description above is in the general context of computer-executable instructions that can run on one or more computers, those skilled in the art will recognize that a novel embodiment also can be implemented in combination with other program modules and/or as a combination of hardware and software. 
         [0045]    The computing system  500  for implementing various aspects includes the computer  502  having processing unit(s)  504 , a computer-readable storage such as a system memory  506 , and a system bus  508 . The processing unit(s)  504  can be any of various commercially available processors such as single-processor, multi-processor, single-core units and multi-core units. Moreover, those skilled in the art will appreciate that the novel methods can be practiced with other computer system configurations, including minicomputers, mainframe computers, as well as personal computers (e.g., desktop, laptop, etc.), hand-held computing devices, microprocessor-based or programmable consumer electronics, and the like, each of which can be operatively coupled to one or more associated devices. 
         [0046]    The system memory  506  can include computer-readable storage such as a volatile (VOL) memory  510  (e.g., random access memory (RAM)) and non-volatile memory (NON-VOL)  512  (e.g., ROM, EPROM, EEPROM, etc.). A basic input/output system (BIOS) can be stored in the non-volatile memory  512 , and includes the basic routines that facilitate the communication of data and signals between components within the computer  502 , such as during startup. The volatile memory  510  can also include a high-speed RAM such as static RAM for caching data. 
         [0047]    The system bus  508  provides an interface for system components including, but not limited to, the system memory  506  to the processing unit(s)  504 . The system bus  508  can be any of several types of bus structure that can further interconnect to a memory bus (with or without a memory controller), and a peripheral bus (e.g., PCI, PCIe, AGP, LPC, etc.), using any of a variety of commercially available bus architectures. 
         [0048]    The computer  502  further includes machine readable storage subsystem(s)  514  and storage interface(s)  516  for interfacing the storage subsystem(s)  514  to the system bus  508  and other desired computer components. The storage subsystem(s)  514  can include one or more of a hard disk drive (HDD), a magnetic floppy disk drive (FDD), and/or optical disk storage drive (e.g., a CD-ROM drive DVD drive), for example. The storage interface(s)  516  can include interface technologies such as EIDE, ATA, SATA, and IEEE 1394, for example. 
         [0049]    One or more programs and data can be stored in the memory subsystem  506 , a machine readable and removable memory subsystem  518  (e.g., flash drive form factor technology), and/or the storage subsystem(s)  514  (e.g., optical, magnetic, solid state), including an operating system  520 , one or more application programs  522 , other program modules  524 , and program data  526 . 
         [0050]    The one or more application programs  522 , other program modules  524 , and program data  526  can include the entities of the system  100  of  FIG. 1 , the schema  200  of  FIG. 2 , and the methods represented by the flow charts of  FIGS. 3-4 , for example. 
         [0051]    Generally, programs include routines, methods, data structures, other software components, etc., that perform particular tasks or implement particular abstract data types. All or portions of the operating system  520 , applications  522 , modules  524 , and/or data  526  can also be cached in memory such as the volatile memory  510 , for example. It is to be appreciated that the disclosed architecture can be implemented with various commercially available operating systems or combinations of operating systems (e.g., as virtual machines). 
         [0052]    The storage subsystem(s)  514  and memory subsystems ( 506  and  518 ) serve as computer readable media for volatile and non-volatile storage of data, data structures, computer-executable instructions, and so forth. Computer readable media can be any available media that can be accessed by the computer  502  and includes volatile and non-volatile internal and/or external media that is removable or non-removable. For the computer  502 , the media accommodate the storage of data in any suitable digital format. It should be appreciated by those skilled in the art that other types of computer readable media can be employed such as zip drives, magnetic tape, flash memory cards, flash drives, cartridges, and the like, for storing computer executable instructions for performing the novel methods of the disclosed architecture. 
         [0053]    A user can interact with the computer  502 , programs, and data using external user input devices  528  such as a keyboard and a mouse. Other external user input devices  528  can include a microphone, an IR (infrared) remote control, a joystick, a game pad, camera recognition systems, a stylus pen, touch screen, gesture systems (e.g., eye movement, head movement, etc.), and/or the like. The user can interact with the computer  502 , programs, and data using onboard user input devices  530  such a touchpad, microphone, keyboard, etc., where the computer  502  is a portable computer, for example. These and other input devices are connected to the processing unit(s)  504  through input/output (I/O) device interface(s)  532  via the system bus  508 , but can be connected by other interfaces such as a parallel port, IEEE 1394 serial port, a game port, a USB port, an IR interface, etc. The I/O device interface(s)  532  also facilitate the use of output peripherals  534  such as printers, audio devices, camera devices, and so on, such as a sound card and/or onboard audio processing capability. 
         [0054]    One or more graphics interface(s)  536  (also commonly referred to as a graphics processing unit (GPU)) provide graphics and video signals between the computer  502  and external display(s)  538  (e.g., LCD, plasma) and/or onboard displays  540  (e.g., for portable computer). The graphics interface(s)  536  can also be manufactured as part of the computer system board. 
         [0055]    The computer  502  can operate in a networked environment (e.g., IP-based) using logical connections via a wired/wireless communications subsystem  542  to one or more networks and/or other computers. The other computers can include workstations, servers, routers, personal computers, microprocessor-based entertainment appliances, peer devices or other common network nodes, and typically include many or all of the elements described relative to the computer  502 . The logical connections can include wired/wireless connectivity to a local area network (LAN), a wide area network (WAN), hotspot, and so on. LAN and WAN networking environments are commonplace in offices and companies and facilitate enterprise-wide computer networks, such as intranets, all of which may connect to a global communications network such as the Internet. 
         [0056]    When used in a networking environment the computer  502  connects to the network via a wired/wireless communication subsystem  542  (e.g., a network interface adapter, onboard transceiver subsystem, etc.) to communicate with wired/wireless networks, wired/wireless printers, wired/wireless input devices  544 , and so on. The computer  502  can include a modem or other means for establishing communications over the network. In a networked environment, programs and data relative to the computer  502  can be stored in the remote memory/storage device, as is associated with a distributed system. It will be appreciated that the network connections shown are exemplary and other means of establishing a communications link between the computers can be used. 
         [0057]    The computer  502  is operable to communicate with wired/wireless devices or entities using the radio technologies such as the IEEE 802.xx family of standards, such as wireless devices operatively disposed in wireless communication (e.g., IEEE 802.11 over-the-air modulation techniques) with, for example, a printer, scanner, desktop and/or portable computer, personal digital assistant (PDA), communications satellite, any piece of equipment or location associated with a wirelessly detectable tag (e.g., a kiosk, news stand, restroom), and telephone. This includes at least Wi-Fi (or Wireless Fidelity) for hotspots, WiMax, and Bluetooth™ wireless technologies. Thus, the communications can be a predefined structure as with a conventional network or simply an ad hoc communication between at least two devices. Wi-Fi networks use radio technologies called IEEE 802.11x (a, b, g, etc.) to provide secure, reliable, fast wireless connectivity. A Wi-Fi network can be used to connect computers to each other, to the Internet, and to wire networks (which use IEEE 802.3-related media and functions). 
         [0058]    What has been described above includes examples of the disclosed architecture. It is, of course, not possible to describe every conceivable combination of components and/or methodologies, but one of ordinary skill in the art may recognize that many further combinations and permutations are possible. Accordingly, the novel architecture is intended to embrace all such alterations, modifications and variations that fall within the spirit and scope of the appended claims. Furthermore, to the extent that the term “includes” is used in either the detailed description or the claims, such term is intended to be inclusive in a manner similar to the term “comprising” as “comprising” is interpreted when employed as a transitional word in a claim.