biogeme.models.logit module

Implements the logit model.

author:

Michel Bierlaire

date:

Wed Oct 25 08:43:26 2023

biogeme.models.logit.logit(util, av, i)[source]

The logit model

The model is defined as

aieVii=1JajeVj
Parameters:
  • util (dict[int, Expression | float | int | bool]) – dict of objects representing the utility functions of each alternative, indexed by numerical ids.

  • av (dict[int, Expression | float | int | bool] | None) – dict of objects representing the availability of each alternative (ai in the above formula), indexed by numerical ids. Must be consistent with util, or None. In this case, all alternatives are supposed to be always available.

  • i (Expression | float | int | bool) – id of the alternative for which the probability must be calculated.

Return type:

Expression

Returns:

choice probability of alternative number i.

biogeme.models.logit.loglogit(util, av, i)[source]

The logarithm of the logit model

The model is defined as

aieVii=1JajeVj
Parameters:
  • util (dict[int, Expression | float | int | bool]) – dict of objects representing the utility functions of each alternative, indexed by numerical ids.

  • av (dict[int, Expression | float | int | bool] | None) – dict of objects representing the availability of each alternative (ai in the above formula), indexed by numerical ids. Must be consistent with util, or None. In this case, all alternatives are supposed to be always available.

  • i (Expression | float | int | bool) – id of the alternative for which the probability must be calculated.

Return type:

Expression

Returns:

choice probability of alternative number i.