A holding unit of an information processing apparatus holds a classification model and characteristic information for each of a plurality of groups acquired by dividing a plurality of feature values extracted from a plurality of training data pieces belonging to a specific class. Then, a feature extraction unit extracts a feature value from input data, and a selection unit selects one or more group(s) from the plurality of groups based on this extracted feature value and the characteristic information held by the holding unit. Then, a determination unit determines whether the input data belongs to the specific class with use of the classification model(s) corresponding to the selected group(s).
Please help me write a proper abstract based on the patent claims. CLAIM: 1. An information processing apparatus comprising: a feature extraction unit configured to extract a feature value from input data; a holding unit configured to, with respect to each of a plurality of groups acquired by dividing a plurality of feature values extracted from a plurality of training data pieces belonging to a specific class, hold characteristic information indicating a characteristic of a corresponding one of the plurality of groups, and a classification model; a selection unit configured to select at least one group from the plurality of groups held by the holding unit based on the extracted feature value of the input data and the characteristic information; and a determination unit configured to determine whether the input data belongs to the specific class with use of the classification model corresponding to the at least one group selected by the selection unit. 2. The information processing apparatus according to claim 1, wherein the determination unit determines, on the at least one group selected by the selection unit, whether the input data belongs to the specific class with use of the classification model corresponding to the at least one group selected by the selection unit, and wherein, in a case where the determination unit determines that the input data belongs to the specific class in any of the selected groups, the determination unit determines that the input data belongs to the specific class. 3. The information processing apparatus according to claim 1, wherein the plurality of feature values is divided into the plurality of groups based on information relating to an environment under which the training data is acquired, and wherein the holding unit holds the information relating to the environment under which the training data is acquired for each of the plurality of groups. 4. The information processing apparatus according to claim 3, wherein the selection unit acquires the information relating to an environment under which the input data is acquired, and selects the at least one group based on the feature value extracted from the input data and the information relating to an environment under which the input data is acquired. 5. The information processing apparatus according to claim 1, further comprising: a characteristic information setting unit configured to divide the plurality of feature values extracted from the plurality of training data pieces into the plurality of groups, and set the characteristic information of each of the plurality of groups; and a classification model generation unit configured to, with respect to each of the plurality of groups, generate the classification model based on feature value(s) included in a corresponding one of the plurality of groups. 6. The information processing apparatus according to claim 5, wherein the classification model generation unit randomly generates candidates for the classification model according to a predetermined probability distribution, with respect to each of the plurality of groups, and selects a candidate for the classification model that allows feature value(s) belonging to a corresponding one of the plurality of groups to be classified as the specific class and a density of the feature value(s) in the specific class to exceed a predetermined value, in each of the plurality of groups. 7. The information processing apparatus according to claim 6, wherein the probability distribution is set for each of the plurality of groups based on the characteristic information. 8. The information processing apparatus according to claim 6, wherein the classification model generation unit selects the candidate for the classification model further based on a degree of similarity between the candidates for the classification model. 9. The information processing apparatus according to claim 5, wherein the classification model generation unit includes an importance assignment unit configured to, based on the classification model already generated for each of the plurality of groups and the feature value(s) belonging to a corresponding one of the plurality of groups, assign importance to the feature value(s), a model addition determination unit configured to determine whether to add the classification model to the group based on the importance assigned by the importance assignment unit, and a model addition unit configured to add the classification model based on the importance assigned by the importance assignment unit and the feature value(s) belonging to the corresponding one of the plurality of groups, in a case where the model addition determination unit determines to add the classification model to the corresponding one of the plurality of groups. 10. The information processing apparatus according to claim 1, wherein the characteristic information is a central coordinate of a plurality of feature values included in a corresponding one of the plurality of group in a feature space, or a variance-covariance matrix corresponding to the group. 11. An information processing method in an information processing apparatus including a holding unit configured to, with respect to each of a plurality of groups acquired by dividing a plurality of feature values extracted from a plurality of training data pieces belonging to a specific class, hold characteristic information indicating a characteristic of a corresponding one of the plurality of groups, and a classification model, the information processing method comprising: extracting a feature value from input data; selecting at least one group from the plurality of groups held by the holding unit based on the extracted feature value of the input data and the characteristic information; and determining whether the input data belongs to the specific class with use of the classification model corresponding to the at least one group selected by the selecting. 12. A non-transitory computer-readable recording medium that stores a program for causing a computer to function as the units of an information processing apparatus comprising: a feature extraction unit configured to extract a feature value from input data; a holding unit configured to, with respect to each of a plurality of groups acquired by dividing a plurality of feature values extracted from a plurality of training data pieces belonging to a specific class, hold characteristic information indicating a characteristic of a corresponding one of the plurality of group, and a classification model; a selection unit configured to select at least one group from the plurality of groups held by the holding unit based on the extracted feature value of the input data and the characteristic information; and a determination unit configured to determine whether the input data belongs to the specific class with use of the classification model corresponding to the at least one group selected by the selection unit.