blorr: blr_step_p_backward – R documentation

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blr_step_p_backward

Stepwise backward regression

Description

Build regression model from a set of candidate predictor variables by removing predictors based on p values, in a stepwise manner until there is no variable left to remove any more.

Usage

blr_step_p_backward(model, ...)

## Default S3 method:
blr_step_p_backward(model, prem = 0.3, details = FALSE, ...)

## S3 method for class 'blr_step_p_backward'
plot(x, model = NA, print_plot = TRUE, ...)

Arguments

`model`	An object of class `lm`; the model should include all candidate predictor variables.
`...`	Other inputs.
`prem`	p value; variables with p more than `prem` will be removed from the model.
`details`	Logical; if `TRUE`, will print the regression result at each step.
`x`	An object of class `blr_step_p_backward`.
`print_plot`	logical; if `TRUE`, prints the plot else returns a plot object.

Value

blr_step_p_backward returns an object of class "blr_step_p_backward". An object of class "blr_step_p_backward" is a list containing the following components:

`model`	model with the least AIC; an object of class `glm`
`steps`	total number of steps
`removed`	variables removed from the model
`aic`	akaike information criteria
`bic`	bayesian information criteria
`dev`	deviance
`indvar`	predictors

References

Chatterjee, Samprit and Hadi, Ali. Regression Analysis by Example. 5th ed. N.p.: John Wiley & Sons, 2012. Print.

Examples

## Not run: 
# stepwise backward regression
model <- glm(honcomp ~ female + read + science + math + prog + socst,
  data = hsb2, family = binomial(link = 'logit'))
blr_step_p_backward(model)

# stepwise backward regression plot
model <- glm(honcomp ~ female + read + science + math + prog + socst,
  data = hsb2, family = binomial(link = 'logit'))
k <- blr_step_p_backward(model)
plot(k)

# final model
k$model


## End(Not run)

blorr

Tools for Developing Binary Logistic Regression Models

v0.3.0

MIT + file LICENSE

Authors

Aravind Hebbali [aut, cre] (<https://orcid.org/0000-0001-9220-9669>)

Initial release