Patent Publication Number: US-8117063-B2

Title: System and methods for creating probabilistic products and for facilitating probabilistic selling

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 60/866,008 filed Nov. 15, 2006, which is incorporated herein in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The present invention is related to the fields of product generation and marketing, and more particularly, to techniques for creating probabilistic products and for facilitating the selling of such products. 
     BACKGROUND OF THE INVENTION 
     Providers of products and services face many challenges in marketing their respective products and services in a market-based economy. Because different consumers typically value the same product or service differently, one challenge for a provider is to distinguish between those consumers who place a higher value on a product or service from those consumers whose subjective valuation of the product or service is lower. 
     One technique for enlarging a provider&#39;s “producer surplus” is price discrimination. With price discrimination, those consumers whose subjective valuation of a product or service is higher are charged a higher price, while those consumers who place a lower value on a product or service are charged a lower price. Price discrimination can be effected, for example, using product lines, according to which different versions of the same basic product are offered by varying one or more attributes of the product. For example, a linen seller might offer multiple versions of bed sheets by varying the thread count so that a higher price could be obtained from consumers desiring a 500-thread count than that obtained from consumers who are content with only a 250-thread count. Accordingly, product lines can allow a seller to achieve higher unit sales (e.g., by allowing the seller to attract low-valuation customers) and/or allow the seller to generate higher average revenue per sale (e.g., by inducing high-valuation customers to pay higher prices.) The same technique can be applied in order to achieve price discrimination in the context of providing a particular service. 
     One disadvantage of product lines, however, is that compared to single products, multiple products can be much more expensive to create and sell. This primarily is because offering a product line with different versions of the same underlying product (e.g., sheets having different thread counts) requires separate design, manufacturing, marketing, and distribution processes for each of the products in the line. Another disadvantage to attempting to achieve price discrimination by offering a product line is that the strategy can diminish the producer&#39;s ability to benefit from economies of scale. For example, if unit cost declines with output, then producing 2,000 bed sheets that have a 500 thread count may be less costly than producing 1,000 units with a 500-thread count and 1,000 units with a 250-thread count. 
     Other mechanisms for price discrimination include techniques such as offering coupons, rebates, volume discounts, and/or senior discounts. Each of the mechanisms, however, has its own limitations or disadvantages. For example, senior discounts unnecessarily and likely sub-optimally provide discounts even to those seniors who are not sensitive to the product&#39;s price. 
     Another challenge facing product and service providers is demand uncertainty. The problem arises because it is often difficult for the producer to accurately predict future consumer demand for a particular product or service. If demand is unknown, the producer is more likely to sub-optimally set the asking price for the product or service. For example, a seller of handbags would ordinary prefer to set a higher price for handbags of a certain type or style that is likely to be this season&#39;s more fashionable one, while setting a lower price for less fashionable versions. Without being able to predict which version will be more fashionable, however, the seller&#39;s ability to set an optimal price at the outset is significantly constrained. 
     Moreover, when a seller has limited capacity, demand uncertainty can result in too much or too little of a product being produced or inventoried. In the event of the former, the seller typically endures the expense of producing unsold goods and possibly the cost of carrying excess inventory, whereas the latter event denies the seller the opportunity to fully exploit current market demand. 
     Various mechanisms for dealing with demand uncertainty have been proposed. For example, the airline industry has implemented sophisticated yield-management systems in an attempt to adjust prices over time so as to obtain the maximum revenue given a limited number of seats available for any particular flight. Nonetheless, the mechanisms are typically quite costly to design and implement. 
     Accordingly, there is a need for more effective and efficient mechanisms for dealing with these and other challenges facing product and service providers operating in a market-based economy. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to systems and methods for creating probabilistic products. A probabilistic product is one for which a seller offers a potential buyer a gamble, namely, that of paying a set price in return for receiving one item drawn from a set of distinct items. The invention also is directed to systems and methods for facilitating probabilistic selling. 
     One embodiment of the invention is a method for creating a probabilistic product by varying one or more values of one or more predefined critical variables. The method can include creating a set of product identifiers corresponding to a plurality of products, each of the plurality of product identifiers uniquely corresponding to one of the plurality of products. The method also can include selecting a subset of the product identifiers. Additionally, the method can include generating a plurality of probability values, each probability value uniquely corresponding to one of the product identifiers contained in the subset, wherein the sum of the probability values equals one. The method further can include determining a monetary value, the value defining a selling price, wherein by paying the selling price to the seller, a buyer subsequently receives a product associated with one of the product identifiers randomly chosen from the subset, and wherein the probability of choosing a particular product identifier is equal to the probability value corresponding to the particular product identifier. The subset and corresponding probabilities define a single probabilistic product. 
     Another embodiment of the invention is a method of creating a probabilistic product by selecting a plurality of products from among an inventory of products offered by a single seller. The method can include associating a plurality of product identifiers with the selected plurality of products, each of the plurality of product identifiers uniquely corresponding to one of the plurality of products. The method further can include assigning a plurality of probability values, each probability value uniquely corresponding to one of the product identifiers. 
     The method, according to this embodiment, can additionally include determining a monetary value that defines or equals a selling price, wherein by paying the monetary value to the seller, a buyer will receive a product associated with one of the product identifiers randomly chosen from the subset, and wherein the probability of choosing a particular product identifier is equal to the probability value corresponding to the particular product identifier. Furthermore, according to this embodiment, the selling price can be determined based upon how many products are selected and/or the probabilities corresponding to each of the products selected. 
     Still another embodiment of the invention is a method for creating a probabilistic product by varying a plurality of predefined critical variables. The method can include creating a set of product identifiers corresponding to a plurality of products, each of the plurality of product identifiers uniquely corresponding to one of the plurality of products. Additionally, the method can include selecting a subset of the product identifiers, and generating a plurality of probability values, each of which uniquely corresponds to one of the product identifiers contained in the subset. The method also can include determining a monetary value, defining a selling price, wherein by paying the selling price to the seller a buyer will receive a product associated with one of the product identifiers randomly chosen from the subset, and wherein the probability of choosing a particular product identifier is equal to the probability value corresponding to the particular product identifier. 
     According to this particular embodiment, the method further can include conveying to a plurality of buyers at different network-connected nodes over a data communications network an offer for the probabilistic product, tracking each purchase of the probabilistic product, and storing related transactions information associated with each purchase. Additionally, the method can include selectively providing access to the related transactions information. 
     Yet another embodiment of the invention is a method of monitoring the selling of a probabilistic product. The method can include tracking purchases of at least one probabilistic product offered by at least one seller, the at least one probabilistic product being defined by a plurality of distinct products and a plurality of probabilities associated therewith, each of the probabilities uniquely corresponding to one of the distinct products. The method further can include generating transaction information associated with each of the purchases tracked. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       There are shown in the drawings, embodiments which are presently preferred. It is expressly noted, however, that the invention is not limited to the precise arrangements and instrumentalities shown. 
         FIG. 1  is a schematic view of an exemplary environment in which a system for creating probabilistic products, according to one embodiment of the invention, is utilized. 
         FIG. 2  is a schematic view of various aspects of creating a probabilistic product according one embodiment of the invention. 
         FIG. 3  is a schematic view of a system for creating probabilistic products, according to one embodiment of the invention. 
         FIG. 4  is a schematic view of an exemplary environment in which a system for monitoring probabilistic selling, according to another embodiment of the invention, is utilized. 
         FIG. 5  is a schematic view of a system for monitoring probabilistic selling, according to another embodiment of the invention. 
         FIG. 6  is a flowchart of exemplary steps in a method for creating a probabilistic product, according still another embodiment of the invention. 
         FIG. 7  is a flowchart of exemplary steps in a method for monitoring probabilistic selling, according yet another embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION 
     The invention is directed to systems and methods for facilitating probabilistic selling. One aspect of the invention is a system and methods for creating probabilistic products. Another aspect of the invention is a technique for enhancing the seller&#39;s ability to sell probabilistic products by establishing the seller&#39;s credibility among actual and potential buyers of probabilistic products. 
     As described herein, the seller of a probabilistic product offers a potential buyer the opportunity to obtain one item drawn from a set of distinct items. According to one embodiment of the invention, the probability of obtaining any particular item is known to the potential buyer in advance. In an alternate embodiment, however, the probability of obtaining any particular item is not known to the potential buyer in advance. 
     The items can be different products or, alternatively, each can be the same basic product but having different attributes. For example, the probabilistic product could comprise different versions of a handbag, the different versions being distinguished according to color and/or quality of material. A purchaser of such a product could have, for example, a twenty percent chance of receiving a black handbag and/or one made of high-quality material, a thirty percent chance of receiving a grey handbag and/or one made of medium-quality material, and a fifty percent chance of receiving a brown handbag and/or one made of low-quality material. 
     Although the term “product” is used in the present description, it is explicitly noted that the term is intended to encompass services as well as products. Indeed, a probabilistic product alternately can be an event outcome. For example, the probabilistic product can comprise a set of tickets, each of the tickets being for admission to the same show on a different night or different shows on the same or different nights. Similarly, the probabilistic product could be a set of class registrations for university students, each registration being for a particular class at different times and/or taught by different professors, or for different classes taught at the same time and/or by the same professor. 
     Accordingly, there are an unlimited number of different probabilistic products that can be created according to the invention described herein. One defining characteristic of all probabilistic products, according to the invention, is that the probabilistic product, or more particularly, the set of distinct items comprising the probabilistic product, is defined by variable attributes for each item, the different gradations or values of each attribute, and the particular probabilities of drawing any one of the items whose attributes have particular values. As explained herein, different probabilistic products can be created by varying any of these critical variables; that is by varying the number of items, their different attributes, different values for each attribute, and/or probabilities associated with drawing items having particular values for each attribute. 
       FIG. 1  is a schematic diagram of an exemplary environment  100  in which a system  102  for creating probabilistic products, according to one embodiment, is utilized. The exemplary environment  100  illustratively includes a computer  104  on which the system  102 , which is described more particularly below, resides. Additionally, the exemplary environment  100  illustratively includes one or more other computers  104  that link directly or via a data communications network  106  comprising a plurality of intermediate nodes to the computer  104  on which the system  102  resides. 
     Accordingly, the system  102  can comprise one or more software modules configured to execute on a general-purpose or application-specific computer based, for example, on the known von Neumann architecture. Accordingly, the system can comprise computer-readable code comprising a set of instructions that when loaded onto and executed by a computing device causes the device to perform the processes and functions described herein. Thus, such software modules can provide the needed functionality for creating probabilistic products, according to one embodiment of the invention. In an alternative embodiment, however, system  102  can be implemented in dedicated hardwired circuitry for performing the functions of the system. In yet another embodiment, the system  102  can be implemented as a combination of software code and hardwired circuitry. 
     Referring additionally to  FIG. 2 , the operative procedures  200  performed by the system  102  are schematically illustrated. Initially, a set of product identifiers  202  is created, the product identifiers corresponding to a plurality of items or products  204  offered by a single seller. The set of product identifiers  202  are used to identify distinct items or products among the plurality of items or products  204 . Accordingly, the system  102  associates the product identifiers with the distinct products such that each product identifier uniquely corresponds to a particular one of the plurality of products  204 . 
     As already described, each item or product belonging to an item set comprising the probabilistic product can be a different product or a different version of the same product, each version having one or more attributes whose particular value or values are different from those of other products in the set. Accordingly, each product identifier associated with a particular product can be a scalar number or alphanumeric characters that uniquely identifies the particular product. For example, such a product identifier can be a stock keeping unit (SKU), as will be readily understood by one of ordinary skill in the art. 
     In another embodiment, however, the set of product identifiers  202  can comprise a set of n-tuples, or attribute vectors. For example, the i-th product identifier corresponding to the i-th product having n different attributes could be represented as follows:
 
Prod_Id i   =&lt;a   1   ,a   2   , . . . a   n &gt;,
 
where each a k , 1≦k≦n, can take a different value depending on the number of different values are assigned to the k-th attribute of the i-th product. As described below, according to the invention, there is a probability (perhaps zero) that the buyer of the probabilistic product will receive a product described by any particular n-tuple. The probabilities are assigned by the system  102 , as also described below.
 
     The system  102  then selects a subset of the product identifiers  206 , illustratively comprising Id i , Id j , . . . , Id k . For the product identifiers contained in the subset  206 , the system  102  generates a plurality of probability values  208  such that each probability value uniquely corresponds to one of the product identifiers contained in the subset, and such that the sum of the probability values equals one: 
     
       
         
           
             
               
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                 Prob 
                 ⁡ 
                 
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             = 
             1. 
           
         
       
     
     The probability values corresponding to the exemplary subset are schematically shown as Prob i , Prob j , . . . , Prob k . As already noted, each of the product identifiers can comprise an n-tuple or product vector, each element of which corresponds to a particular value for each of a plurality of attributes. Accordingly, each such probability can comprise a multivariate probability value corresponding to a multivariable probability distribution. 
     The probabilistic product created by the system  102  is accordingly defined by the products corresponding to the identifiers in the subset  206  and their respective corresponding probabilities. By paying the seller&#39;s price for the probabilistic product, a buyer will receive that product associated with one of the product identifiers randomly chosen from the subset, wherein the probability of choosing a particular product identifier is equal to the probability value corresponding to that particular product identifier. 
     Different combinations of products, identified by the associated product identifiers, give rise to distinct probabilistic products. Thus, for example, by selecting i products to include in the subset, a seller of n distinct products can arrive at the following number of different probabilistic products: 
               (         n           i         )     =         n   !           (     n   -   i     )     !     ⁢     i   !         .           
The number of distinct probabilistic products, moreover, increases by varying the number of products i, 2≦i≦n, included in the subset and well as the respective probabilities, subject to the constraint that the sum of probabilities equals one.
 
     Accordingly, the identity of the products, the number of products, and the respective probabilities, each define critical variables. By modifying one or more of the critical variables, the system  102  can generate different probabilistic products. 
     The system  102 , moreover, can determine a monetary value, defining a selling price, for a particular probabilistic product. The price can be based upon one or more of the critical values, or upon other factors 
     A high-level view of one embodiment of the system  102  is schematically illustrated in  FIG. 3 . The system  102  comprises a plurality of software modules that reside within a computer  300 . The computer  300  illustratively includes a processor  302  and memory  304 , which stores the modules of the system  102  as program instructions that when transferred by a conventional bus (not shown) to the process can be executed to carry out the procedures already described. Illustratively, the system  102  includes an identifier-generating module  306  for creating a set of product identifiers corresponding to a plurality of products offered by a single seller, wherein each of the plurality of product identifiers uniquely corresponds to one of the plurality of products. The system  102  also illustratively includes a selecting module  308  for selecting a subset of the product identifiers. Additionally the system illustratively includes a probability-generating module  310  for generating a plurality of probability values, each probability value uniquely corresponding to one of the product identifiers contained in the subset, wherein the sum of the probability values equals one. 
     As already noted, the subset and corresponding probabilities define a single probabilistic product. The probabilistic product can be generated based upon user input supplied to the system  102  through an interface or I/O device  314  communicatively linking the user to the computer  300 . By varying the critical inputs defined above and inputting the changes via the I/O device  314 , the system  102  can select a plurality of subsets, repeatedly performing for each the generating and determining procedures described above so as to generate a plurality of different probabilistic products. When the computer is connected to a data communications network, offers for one or more probabilistic products can be communicated to a plurality of buyers at different network-connected nodes communicatively linked to the data communications network. 
     Optionally, the system  102  can include a value-determining module  312  for determining a monetary value. The monetary value is a selling price, wherein, by paying the selling price, a buyer will receive a product associated with one of the product identifiers randomly chosen from the subset. Moreover, the probability of choosing a particular product identifier is equal to the probability value corresponding to the particular product identifier. In an alternative embodiment, the system  102  can include a value-determining module that is specifically configured to determine the selling price, wherein the selling price is specifically determined based upon how many products are selected and/or the probabilities corresponding to each of the products selected. 
     According to one embodiment, the seller determines (1) how many products are selected, (2) which products are selected, and/or (3) the probability values assigned to each product selected. If the seller determines each of the critical variables, the seller can convey an offer that includes information informing the buyer of less than all the critical variables. The price can vary accordingly so as to make the probabilistic purchase still valuable to at least some buyers. 
     In an alternate embodiment it is the buyer who determines one or more of these critical values. The buyer, more particularly, can effect the determination in response to an offer conveyed to a plurality of network-connected nodes communicatively linked to a data communications network. 
       FIG. 4  is a schematic view of an exemplary environment  400  in which a system  402  for monitoring the selling of a probabilistic product, according to another embodiment, is utilized. The exemplary environment  400  illustratively includes a computer  404  on which the system  402  resides. The computer is illustratively linked to a plurality of other computers  406  via a data communications network  408 . Additionally, the computer  404  and each of the other computers  406  are linked to a database  410  via the data communications network  408 . 
     Referring additionally to  FIG. 5 , the system  402  is schematically shown as comprising distinct software modules configured to be executed by a processor  502  and stored in a memory  504  of the computer  404 . The software modules comprise computer instructions for performing functions for monitoring selling of a probabilistic product. In alternative embodiments, however, the modules can be implemented in dedicated, hardwired circuitry or a combination of hardwired circuitry and software code. 
     The system  402  illustratively includes a tracking module  506  for tracking purchases of at least one probabilistic product offered by at least one seller, the at least one probabilistic product being defined by a plurality of distinct products and a plurality of probabilities associated therewith, wherein each of the probabilities uniquely corresponds to one of the distinct products. Additionally, the system  402  illustratively includes an information-generating module  508  for generating transaction information associated with each of the purchases tracked. 
     The information-generating module  508  can be configured to generate transaction information by determining, for each purchase of one or more probabilistic products, which of the plurality of products was provided to a buyer. The purchases can be tracked and the information generated based upon data received via an I/O device  514  of the computer  404  and/or data received over a connection to the other computers  406  when connected via the data communications network  408 . 
     According to a particular embodiment, the system  402  can be maintained and operated by an entity independent of the sellers whose sales of probabilistic products the entity monitors. The independent entity, moreover, can be tasked with randomly choosing a particular product from among the plurality of distinct products according to the probabilities associated therewith. Additionally, the independent entity can, according to another embodiment, determine when a seller and a buyer have agreed upon a price for at least one probabilistic product. In response, the entity can randomly choose a particular product. The independent entity also can be tasked with providing to the buyer the particular product randomly chosen according to the described procedure. 
     The entity thus can be an intermediary that specializes in directly making product assignments for one or more sellers that offer probabilistic products. The entity can collect and provide related information to consumers. One of the benefits provided through such an arrangement is that it can enhance the credibility of the seller or sellers that are independently monitored. 
     In particular, once a seller and buyer commit to a particular probabilistic product at a particular price, relevant information can be sent to the entity. Acting as both parties&#39; intermediary, the entity can select the product, randomly, and then inform both the buyer and the seller of the outcome of the entities&#39; random selection. Acting in this fashion, the entity provides assurance that the transaction for the probabilistic product is consummated with integrity; the entity is invested in its own reputation and is thus less likely than an interested party to deviate from the terms of the transaction when the random selection of the actual product is made. 
     Whether obtained by the seller or an independent entity, related transaction information such as the history of past product transactions and assignments can be stored in a network-connected database  410 . The database  410  can be accessed at the various computers  406  connected via to the database via the data communications network. The database, by providing relevant transaction information, can enhance a seller&#39;s credibility by providing information about the seller&#39;s past dealings with other buyers of probabilistic products. 
     The invention has thus far been described in the context of a data processing system that, according to one embodiment, can be utilized as part of a data communications network. It is expressly noted, however, that the invention applies more generally. For example, the invention can be implemented using an electronic or even a non-electronic random number generator, such as a conventional die, wherein a customer rolls the die and, depending on the outcome, a salesperson or other entity selects and dispenses the corresponding item drawn from the set of items comprising the probabilistic product. 
     A method aspect of the invention is illustrated by the flowchart of  FIG. 6 . The flowchart includes the exemplary steps of a method  600  for creating a probabilistic product by varying a plurality of predefined critical variables, according to another embodiment of the invention. 
     The method  600  includes, at step  602 , creating a set of product identifiers corresponding to a plurality of products offered by a single seller, wherein each of the plurality of product identifiers uniquely corresponds to one of the plurality of products. The method  600  further includes selecting a subset of the product identifiers at step  604 , and at step  606 , generating a plurality of probability values, each probability value uniquely corresponding one of the product identifiers contained in the subset (the probability values summing to one). The method illustratively concludes at step  608 . 
     Optionally, the method  600  can also include determining a monetary value, defining a selling price. By paying the selling price to the seller, a buyer will receive a product associated with one of the product identifiers randomly chosen from the subset. According to one embodiment, the selling price, moreover, can be determined based upon how many products are selected and the probabilities corresponding to each of the products selected. 
     The probability of choosing a particular product identifier is equal to the probability value corresponding to the particular product identifier, according to the invention. Thus, the subset and corresponding probabilities can define the single probabilistic product created according to the method. The method can further include selecting a new subset and repeating the generating step and determining step to create another probabilistic product. For each probabilistic product created, an offer for the probabilistic product can be conveyed to a plurality of buyers at different network-connected nodes communicatively linked to a data communications network. 
     The amount of information conveyed in the offer, moreover, can vary, and the price of the probabilistic product can be altered according to how much information is provided. The information can include: (1) how many products are selected; (2) which products are selected; and (3) the probability values assigned to each product selected. According to one embodiment, the seller determines each of the variables. In an alternative embodiment, however, the buyer is offered an opportunity to choose one or more of the variables, and by doing so, can affect the selling price. 
     Another method aspect of the invention is a method  700  of monitoring the selling of a probabilistic product, the method illustrated by the exemplary steps of the flowchart of  FIG. 7 . The method  700  illustratively includes tracking purchases of at least one probabilistic product offered by at least one seller at step  702 , wherein the at least one probabilistic product is defined by a plurality of distinct products and a plurality of probabilities associated therewith, each of the probabilities uniquely corresponding to one of the distinct products. The method  700  further illustratively includes, at step  704 , generating transaction information associated with each of the purchases tracked. The step of generating transaction information, according to a particular embodiment, can comprise determining for each purchase of the at least one probabilistic product which of the plurality of products was provided to a buyer. Additionally, or alternately, the step can include generating additional transaction information comprising at least one of (1) the price agreed upon, (2) the product randomly chosen, and (3) the probability corresponding to the random choice, and storing the additional transaction information. The method illustratively concludes at step  706 . 
     According to one embodiment of the invention, the method steps are performed by the seller of the probabilistic product. The seller can provide access to a network-based database that provides to prospective buyers relevant information regarding past purchases by others. 
     Alternatively, however, the method steps can be performed by an independent entity. The entity can further perform the step of randomly choosing a particular product from among the plurality of distinct products according to the probabilities associated therewith. The entity also can determine when the seller and a buyer have agreed upon a price for the at least one probabilistic product and, in response thereto, randomly choose the particular product. Moreover, the entity can provide to a buyer the particular product randomly chosen. 
     One application of the invention is as a marketing technique that offers a number of distinct advantages to a seller. The invention enables a seller to engage in probabilistic selling, which the inventors have shown can be used to create opportunities for price discrimination such that the seller is able to distinguish buyers who have strong preferences from those who have weak preferences across one or more of the attributes of the items comprising a probabilistic product. A discounted probabilistic product can attract buyers with weaker preferences, whereas the products attract buyers with stronger preferences. Probabilistic selling can enable the seller to potentially sell to additional consumers and/or to derive greater consumer surplus per sale, on average. This benefit can be achieved even if all buyers prefer the same product so long as the buyers differ in the strength of these preferences. Because the creation of probabilistic products does not require the development of new physical products, product line extension can be accomplished in a virtual fashion at reduced or minimal cost. 
     Another application of the invention is as a technique for dealing with demand uncertainty. Probabilistic selling can be particularly advantageous for a seller when the seller can not perfectly forecast the individual demand for the different items comprising the probabilistic product. This is because probabilistic selling can mitigate or even eliminate the dependence of a multi-product seller&#39;s pricing decision on demand for each individual item comprising the probabilistic product. Additionally, probabilistic selling can improve capacity usage rates and also ensure that capacity will be reserved for those consumers with strong preferences for a particular item of the probabilistic product. 
     The invention, as already noted, can be realized in hardware, software, or a combination of hardware and software. The invention can be realized in a centralized fashion in one computer system, or in a distributed fashion where different elements are spread across several interconnected computer systems. Any kind of computer system or other apparatus adapted for carrying out the methods described herein is suited. A typical combination of hardware and software can be a general purpose computer system with a computer program that, when being loaded and executed, controls the computer system such that it carries out the methods described herein. 
     The invention, as also noted already, can be embedded in a computer program product, which comprises all the features enabling the implementation of the methods described herein, and which when loaded in a computer system is able to carry out these methods. Computer program in the present context means any expression, in any language, code or notation, of a set of instructions intended to cause a system having an information processing capability to perform a particular function either directly or after either or both of the following: a) conversion to another language, code or notation; b) reproduction in a different material form. 
     The foregoing description of preferred embodiments of the invention has been presented for the purposes of illustration. The description is not intended to limit the invention to the precise forms disclosed. Indeed, modifications and variations will be readily apparent from the foregoing description. Accordingly, it is intended that the scope of the invention not be limited by the detailed description provided herein.