Provided is an information processing apparatus that tests independence between multiple variables, the information processing apparatus including: a discretization section that discretizes at least one numerical variable on the basis of at least one categorical variable, when the categorical variable and the numerical variable are included in at least two dependent variables in a graphical model and a set of conditional variables serving as conditions of independence between the two variables; and a test execution section that executes a test for conditional independence between the two variables by using the categorical variable and a discrete variable which is obtained by discretizing the numerical variable.
Please help me write a proper abstract based on the patent claims. CLAIM: 1. An information processing apparatus that tests independence between multiple variables, the information processing apparatus comprising: a discretization section that discretizes at least one numerical variable on the basis of at least one categorical variable, when the categorical variable and the numerical variable are included in at least two dependent variables in a graphical model and a set of conditional variables serving as conditions of independence between the two variables; and a test execution section that executes a test for conditional independence between the two variables by using the categorical variable and a discrete variable which is obtained by discretizing the numerical variable. 2. The information processing apparatus according to claim 1, wherein when one of the two variables is the categorical variable, the discretization section discretizes the other of the two variables and the numerical variable included in the set of conditional variables, on the basis of one of the two variables. 3. The information processing apparatus according to claim 1, wherein when only any one of variables constituting the set of conditional variables is the categorical variable, the discretization section discretizes the two variables and the other variables constituting the set of conditional variables, as the numerical variables, on the basis of the categorical variable. 4. The information processing apparatus according to claim 1, further comprising a determination section that determines whether or not the independence between the two variables is rejected, in any of the tests for conditional independence between the two variables, when the tests for conditional independence between the two variables are executed by respectively using the two or more categorical variables, wherein when it is determined that the independence between the two variables is rejected, the test execution section terminates execution of the test for conditional independence between the two variables. 5. The information processing apparatus according to claim 4, wherein when both of the two variables are the categorical variables, in any of the tests for conditional independence between the two variables executed by respectively using the two variables, the determination section determines whether or not the independence between the two variables is rejected. 6. The information processing apparatus according to claim 4, wherein when both of the two variables are the numerical variables and the set of conditional variables includes the two or more categorical variables, in any of tests for conditional independence between the two variables executed by respectively using the categorical variables, the determination section determines whether or not the independence between the two variables is rejected. 7. The information processing apparatus according to claim 4, wherein after the tests for conditional independence between the two variables are executed on a predetermined number of pairs of variables, in any of the tests for conditional independence between the two variables executed by respectively using the categorical variables, the determination section determines whether or not the independence between the two variables is rejected. 8. The information processing apparatus according to claim 1, wherein when there is a plurality of the categorical variables which are criteria of discretization, the discretization section discretizes the numerical variable on the basis of the categorical variable which is designated by a user. 9. The information processing apparatus according to claim 1, wherein the categorical variable includes at least a variable which categorizes persons, and wherein the numerical variable includes at least a variable which indicates a numerical value of a human body. 10. The information processing apparatus according to claim 1, wherein the categorical variable includes at least a variable which categorizes either or both of a product and a manufacturing apparatus that manufactures the product, and wherein the numerical variable includes at least a variable which indicates a value relating to either or both of the product and an environment where the product is manufactured. 11. An information processing method of causing an information processing apparatus to test independence between multiple variables, the information processing method comprising: discretizing at least one numerical variable on the basis of at least one categorical variable, when the categorical variable and the numerical variable are included in at least two dependent variables in a graphical model and a set of conditional variables serving as conditions of independence between the two variables; and executing a test for conditional independence between the two variables by using the categorical variable and a discrete variable which is obtained by discretizing the numerical variable. 12. A program causing a computer to execute processes for testing independence between multiple variables, the processes comprising: discretizing at least one numerical variable on the basis of at least one categorical variable, when the categorical variable and the numerical variable are included in at least two dependent variables in a graphical model and a set of conditional variables serving as conditions of independence between the two variables; and executing a test for conditional independence between the two variables by using the categorical variable and a discrete variable which is obtained by discretizing the numerical variable.