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Create Simple Slopes Contrast Matrix (COPE Matrix)

Source: R/gen_contrast_ss.R
gen_contrast_ss.Rd

Create Simple Slopes Contrast Matrix (COPE Matrix)

Usage

gen_contrast_ss(model, x, m = NULL, covariates = 0, digits = 4)

Arguments

model

A fitted model object (lm, glm, lmer, lmerTest, etc.).

x

Character string specifying the focal predictor for the slope (e.g., "yrs.since.phd").

m

Moderator specification:

  • NULL (default): No moderators. Returns overall focal predictor slopes.

  • Named list: list(yrs.service = "sd", rank = "real").

  • Special list with "all": list(all = c(continuous = "sd", factor = "real")).

covariates

Value, summary function, or named list of specific values to hold unspecified covariates constant. Default is 0.

digits

Integer specifying the number of decimal places to round continuous numeric variables in row names. Default is 4.

Value

A numeric matrix where rows correspond to simple slope contrasts at moderator values.

See also

Other contrast or COPE helpers: check_contrast_orthogonality(), gen_contrast_blank(), gen_data_jn(), plot.jn_df(), tidy_es_cope_F(), tidy_es_cope_t()

Examples

fit <- lm(salary ~ yrs.since.phd * yrs.service, data = carData::Salaries)
gen_contrast_ss(fit, x = "yrs.since.phd", m = list(yrs.service = "sd"))
#>                                    (Intercept) yrs.since.phd yrs.service
#> yrs.since.phd@yrs.service==4.6086            0             1           0
#> yrs.since.phd@yrs.service==17.6146           0             1           0
#> yrs.since.phd@yrs.service==30.6206           0             1           0
#>                                    yrs.since.phd:yrs.service
#> yrs.since.phd@yrs.service==4.6086                   4.608586
#> yrs.since.phd@yrs.service==17.6146                 17.614610
#> yrs.since.phd@yrs.service==30.6206                 30.620633