Stratification for Visual Predictive Check (VPC)

Use to specify stratification variables for VPC.

stratify(o, ...)

# S3 method for tidyvpcobj
stratify(o, formula, data = o$data, ...)

Arguments

o

A tidyvpcobj.

...

Other arguments to include.

formula

Formula for stratification.

data

Observed data supplied in observed() function.

Value

Returns updated tidyvpcobj with stratification formula, stratification column(s), and strat.split datasets, which is obs split by unique levels of stratification variable(s). Resulting datasets are of class object data.frame

and data.table.

See also

observed simulated censoring predcorrect binning binless vpcstats

Examples

# \donttest{
require(magrittr)

vpc <- observed(obs_data, x=TIME, y=DV) %>%
    simulated(sim_data, y=DV) %>%
    stratify(~ GENDER) %>%
    binning(NTIME) %>%
    vpcstats()

# Example with 2-way stratification by GENDER and STUDY.

vpc <- vpc %>%
    stratify(~ GENDER + STUDY) %>%
    binning(bin = "centers", centers = c(1,3,5,7,10)) %>%
    vpcstats()
# }