A method for automatic recommendation of complex objects of a predefined field to a user using a recommendation engine, the method including the following steps: the user expresses a need in the form of an input on an interface; the recommendation engine calculates a recommendation as a function of the need expressed by the user; a display displays the recommendation calculated by the recommendation engine; the recommendation engine using a normalized catalogue for the calculation of the recommendation.
Please help me write a proper abstract based on the patent claims. CLAIM: 1. A method for automatic recommendation of complex objects of a predefined field to a user using a recommendation engine, the method comprising: a step according to which the user expresses a need in the form of an input on an interface; a step according to which the recommendation engine calculates a recommendation as a function of the need expressed by the user; a step according to which a display displays the recommendation calculated by the recommendation engine; the recommendation engine using a normalised catalogue for the calculation of the recommendation, the normalised catalogue being obtained by: a step to create an unprocessed catalogue of complex objects of a predefined domain, each complex object having a text description; a step to identify and delete any duplicates among the complex objects of the unprocessed catalogue to obtain a refined catalogue; a step to create a model, called that defines a catalogue ontology, of the predefined domain, the catalogue ontology comprising a hierarchy of first characteristics; an annotation step in which a search is made for at least one manifestation of each first characteristic of the catalogue ontology in the text description of each complex object of the refined catalogue and each complex object of the refined catalogue is annotated with each first characteristic of the catalogue ontology of which at least one first manifestation was found in the text description of said complex object, to obtain a formally defined catalogue; a step to create a model that defines a user ontology, of selection criteria of a complex object of the predefined domain, the user ontology comprising a hierarchy of second characteristics; a step to align the user ontology with the catalogue ontology, in which at least one first characteristic of the catalogue ontology is associated with each second characteristic of the user ontology , the first characteristic having a normalised value quantifying the degree of correspondence of said first characteristic with said second characteristic, to obtain the normalised catalogue. 2. The method according to claim 1, wherein the unprocessed catalogue of complex objects of the predefined domain is obtained by compiling a plurality of catalogues of complex objects of the predefined domain. 3. The method according to claim 1, wherein each first characteristic of the catalogue ontology comprises a definition and one or several examples. 4. The method according to claim 3, wherein a set of simple linguistic signs is associated with each first characteristic of the catalogue ontology, each simple linguistic sign being a linguistic manifestation that is usable to denote or evoke said first characteristic. 5. The method according to claim 3, wherein a set of complex linguistic signs is associated with each first characteristic of the catalogue ontology, each complex linguistic sign contributing to differentiating several first characteristics of the catalogue ontology. 6. The method according to claim 1, wherein the annotation step to annotate each complex object of the refined catalogue with at least one first characteristic of the catalogue ontology comprises the following sub-steps: a first sub-step to annotate each complex object of the refined catalogue with one or several candidate annotations, as a function of correspondences detected between at least one text element of the text description of said complex object and one or several first characteristics of the catalogue ontology; a second sub-step to detect inconsistencies in previously determined candidate annotations to only keep coherent annotations. 7. The method according to claim 6, wherein the second sub-step to detect inconsistencies uses a plurality of incompatibility rules, each incompatibility rule defining: an incompatibility constraint between a first type of annotation and a second type of annotation, and a priority, of the first type of annotation over the second type of annotation, or of the second type of annotation over the first type of annotation, so as to be able to choose the annotation to be kept and the annotation to be deleted if applicable. 8. The method according to claim 6, wherein the annotation step comprises a third completion sub-step to extend coherent annotations with affiliated annotations. 9. The method according to claim 8, wherein the third completion sub-step uses a plurality of implication rules, each implication rule being used to test the existence of a first type of annotation for a complex object and if applicable to annotate said complex object with a second type of annotation complementary to the first type of annotation. 10. The method according to claim 1, wherein the step to align the user ontology with the catalogue ontology is done manually. 11. The method according to claim 1, wherein the predefined domain is the domain of games and toys, and the complex objects are games or toys. 12. An automatic recommendation system for complex objects to a user, comprising: a first module for generation of an unprocessed catalogue of complex objects of the predefined domain, each complex object having a text description; a second cleaning module, accepting said unprocessed catalogue as input and returning a refined catalogue as output, the second module comprising means of identifying and eliminating any duplicates among the complex objects of the unprocessed catalogue; a third module to generate a formal definition, that defines a catalogue ontology, of the predefined domain the catalogue ontology comprising a hierarchy of first characteristics; a fourth formalisation module, accepting the refined catalogue and the catalogue ontology as input and returning a formally defined catalogue as output, the fourth module comprising means of annotating each complex object of the refined catalogue with at least one first characteristic of the catalogue ontology; a fifth module to generate a formal definition that defines a user ontology, of selection criteria for a complex object of the predefined domain, the user ontology comprising a hierarchy of second characteristics; a sixth normalisation module accepting the formally defined catalogue and the user ontology as input and returning a normalised catalogue as output, the sixth module comprising means of associating at least one first characteristic of the catalogue ontology with a normalised value quantifying the degree of correspondence of said first characteristic with said second characteristic, with each second characteristic of the user ontology; a recommendation engine accepting the normalised catalogue and an expression of the need of the user in the predefined domain of complex objects as input, said expression comprising at least one second characteristic of the hierarchy of second characteristics of the user ontology, and returning as output a recommendation as a function of said expression and of the normalised catalogue; an interface by which the user inputs the expression of his need in the predefined domain of complex objects; a display that displays the recommendation returned by the recommendation engine. 13. A machine readable medium including a computer program that comprises machine executable instructions for implementing the steps in the automatic method according to claim 1.