To provide a logistic regression analysis system and a logistic regression analysis program for performing logistic regression analysis by using the variable category of explanation variables corresponding to a data category whose composition ratio in a data item is small.

An abnormality detection system 10 as a logistic regression analysis system includes: a determination part 15a for determining whether or not it is possible to input the variable category of explanation variables to a logistic regression function on the basis of the composition ratio of the data category of a data item; a probability calculation part 15b for calculating probability that an event has occurred in the past by using the data category of the data item corresponding to the variable category whose input is determined to be impossible as an object; an integer integration part 15c for integrating this probability into an integer by a predetermined multiple; and a development part 15d for generating the conversion value of the variable category of the explanation variables by developing the probability integrated into an integer on the basis of the validity of the explanation variables of the variable category.