backward_step

<p>Internal function that does the backward step for the stepwise IM function.
#@param empty_start_dataset If TRUE, the initial dataset is empty.
#@param fit Current best fit.
#@param ... Same parameters as in the stepwise function.</p>

internal

Constructs genotype x environment interaction (GxE) models where
G is a weighted sum of genetic variants (genetic score) and E is a weighted
sum of environments (environmental score) using the alternating optimization algorithm
by Jolicoeur-Martineau et al. (2017) <arXiv:1703.08111>. This approach has greatly
enhanced predictive power over traditional GxE models which include only a single
genetic variant and a single environmental exposure. Although this approach was
originally made for GxE modelling, it is flexible and does not require the use of
genetic and environmental variables. It can also handle more than 2 latent variables
(rather than just G and E) and 3-way interactions or more. The LEGIT model produces
highly interpretable results and is very parameter-efficient thus it can even be
used with small sample sizes (n < 250). Tools to determine the type of interaction
(vantage sensitivity, diathesis-stress or differential susceptibility), with any
number of genetic variants or environments, are available <arXiv:1712.04058>. The
software can now produce mixed-effects LEGIT models through the lme4 package.

Alexia Jolicoeur-Martineau

LEGIT

Latent Environmental & Genetic InTeraction (LEGIT) Model

backward_step function

Internal function that does the backward step for the stepwise IM function.
#@param empty_start_dataset If TRUE, the initial dataset is empty.
#@param fit Current best fit.
#@param ... Same parameters as in the stepwise function. — backward_step

Internal function that does the backward step for the stepwise IM function.
#@param empty_start_dataset If TRUE, the initial dataset is empty.
#@param fit Current best fit.
#@param ... Same parameters as in the stepwise function.

backward_step: Internal function that does the backward step for the stepwise IM function. #@param empty_start_dataset If TRUE, the initial dataset is empty. #@param fit Current best fit. #@param ... Same parameters as in the stepwise function.

Description

Usage

Arguments

Value