| center_lm | Center variables in fitted regression models |
| gscale | Scale and/or center regression inputs, including from survey designs, by dividing by 2 SD |
| interact_plot | Plot interaction effects in regression models |
| johnson_neyman | Calculate Johnson-Neyman intervals for 2-way interactions |
| j_summ | Regression summaries with options |
| j_summ.glm | Regression summaries with options |
| j_summ.lm | Regression summaries with options |
| j_summ.svyglm | Regression summaries with options |
| probe_interaction | Probe interaction effects via simple slopes and plotting |
| scale_lm | Scale variables in fitted regression models |
| sim_slopes | Perform a simple slopes analysis |
| svycor | Calculate Pearson correlations with complex survey data |
| svysd | Calculate standard deviations with complex survey data |
| theme_apa | Format ggplot2 figures in APA style |
| wgttest | Test whether sampling weights are needed |