This class gathers the components needed by biogeme to perform the estimation or the simulation. More...
Public Member Functions | |
def | __init__ |
def | __once__ |
Static Public Attributes | |
ESTIMATE = None | |
Expression of the likelihood function to be maximized. | |
SIMULATE = None | |
Enumerate expression to perform sample enumeration. | |
EXCLUDE = None | |
Expression identifying the observations to be ignored in the data file. | |
WEIGHT = None | |
Expression computing the weight of each observation, for WESML. | |
VARCOVAR = None | |
Not implemented. | |
dictionary | STATISTICS = {} |
Dictionary of expressions computing statistics on the data. | |
dictionary | CONSTRAINTS = {} |
Dictionary of expressions defining constraints on the parameters to be estimated. | |
dictionary | PARAMETERS = {} |
Obsolete. |
This class gathers the components needed by biogeme to perform the estimation or the simulation.
def biogeme::BIOGEME_OBJECT::__init__ | ( | self ) |
def biogeme::BIOGEME_OBJECT::__once__ | ( | self ) |
dictionary biogeme::BIOGEME_OBJECT::CONSTRAINTS = {} [static] |
Dictionary of expressions defining constraints on the parameters to be estimated.
In general, it is preferable not to use these constraints. There is most of the time a way to write the model with unconstrained parameters. The two typical examples are:
biogeme::BIOGEME_OBJECT::ESTIMATE = None [static] |
Expression of the likelihood function to be maximized.
Example:
BIOGEME_OBJECT.ESTIMATE = Sum(log(prob),'obsIter')
biogeme::BIOGEME_OBJECT::EXCLUDE = None [static] |
Expression identifying the observations to be ignored in the data file.
Example:
BIOGEME_OBJECT.EXCLUDE = (TRAVEL_TIME < 0)
dictionary biogeme::BIOGEME_OBJECT::PARAMETERS = {} [static] |
Obsolete.
biogeme::BIOGEME_OBJECT::SIMULATE = None [static] |
Enumerate expression to perform sample enumeration.
Example:
simulate = Enumerate('Choice prob.', prob) BIOGEME_OBJECT.SIMULATE = Enumerate(simulate,'obsIter')
dictionary biogeme::BIOGEME_OBJECT::STATISTICS = {} [static] |
Dictionary of expressions computing statistics on the data.
The index of each entry is associated with the value in the report. Example calculating the null loglikelihood of a choice model:
total = 0 for i,a in availability.items() : total += (a != 0) nl = -Sum(log(total),iterator) BIOGEME_OBJECT.STATISTICS['Null loglikelihood'] = nl
biogeme::BIOGEME_OBJECT::VARCOVAR = None [static] |
Not implemented.
biogeme::BIOGEME_OBJECT::WEIGHT = None [static] |
Expression computing the weight of each observation, for WESML.
Typically, a variable in the data file. Example:
BIOGEME_OBJECT.WEIGHT = weight