Learning device, learning method and recording medium

A learning method comprising:

• acquiring learning data including an explanatory variable, an action, and information of outcome of the action;
• and
• learning a model for performing causal inference, using the learning data, based on a loss function partially including a nuisance model which is an estimation object not necessary as a final output,
• wherein the loss function is defined to pessimistically estimate a loss with respect to uncertainty of the nuisance model by using a worst value within a range in which the nuisance model is more certain than a predetermined value.

A non-transitory computer-readable recording medium recording a program, the program causing a computer to execute processing comprising:

• acquiring learning data including an explanatory variable, an action, and information of outcome of the action;
• and
• learning a model for performing causal inference, using the learning data, based on a loss function partially including a nuisance model which is an estimation object not necessary as a final output,
• wherein the loss function is defined to pessimistically estimate a loss with respect to uncertainty of the nuisance model by using a worst value within a range in which the nuisance model is more certain than a predetermined value.