apollo_ownModel {apollo}R Documentation

Calculates own model probabilities

Description

Receives functions or expressions for each functionality so that a user-defined model can interface with Apollo.

Usage

apollo_ownModel(ownModel_settings, functionality)

Arguments

ownModel_settings

List of arguments. Only likelihood is mandatory.

  • gradient: Function or expression used to calculate the gradient of the likelihood. If not provided, Apollo will attempt to calculate it automatically.

  • likelihood: Function or expression used to calculate the likelihood of the model. Should evaluate to a vector, matrix, or 3-dimensional array.

  • prediction: Function or expression used to calculate the prediction of the model. Should evaluate to a vector, matrix, or 3-dimensional array.

  • report: List of functions or expressions used to produce a text report summarising the input and parameter estimates of the model. Should contain two elements: "data" (with a summary of the input data), and "param" (with a summary of the estimated parameters).

  • shares_LL: Function or expression used to calculate the likelihood of the constants-only model.

  • zero_LL: Function or expression used to calculate the likelihood of the base model (e.g. equiprobable model).

functionality

Character. Setting instructing Apollo what processing to apply to the likelihood function. This is in general controlled by the functions that call apollo_probabilities, though the user can also call apollo_probabilities manually with a given functionality for testing/debugging. Possible values are:

  • "components": For further processing/debugging, produces likelihood for each model component (if multiple components are present), at the level of individual draws and observations.

  • "conditionals": For conditionals, produces likelihood of the full model, at the level of individual inter-individual draws.

  • "estimate": For model estimation, produces likelihood of the full model, at the level of individual decision-makers, after averaging across draws.

  • "gradient": For model estimation, produces analytical gradients of the likelihood, where possible.

  • "output": Prepares output for post-estimation reporting.

  • "prediction": For model prediction, produces probabilities for individual alternatives and individual model components (if multiple components are present) at the level of an observation, after averaging across draws.

  • "preprocess": Prepares likelihood functions for use in estimation.

  • "raw": For debugging, produces probabilities of all alternatives and individual model components at the level of an observation, at the level of individual draws.

  • "report": Prepares output summarising model and choiceset structure.

  • "shares_LL": Produces overall model likelihood with constants only.

  • "validate": Validates model specification, produces likelihood of the full model, at the level of individual decision-makers, after averaging across draws.

  • "zero_LL": Produces overall model likelihood with all parameters at zero.

Value

The returned object depends on the value of argument functionality as follows.


[Package apollo version 0.3.5 Index]