Creates a summary object that produces detailed output when printed, including group descriptives, test results with both variance assumptions, effect sizes, and confidence intervals.
Usage
# S3 method for class 't_test'
summary(
object,
descriptives = TRUE,
results = TRUE,
effect_sizes = TRUE,
digits = 3,
...
)Arguments
- object
A
t_testresult object.- descriptives
Logical. Show group descriptive statistics? (Default: TRUE)
- results
Logical. Show test results table? (Default: TRUE)
- effect_sizes
Logical. Show effect size measures? (Default: TRUE)
- digits
Number of decimal places for formatting (Default: 3).
- ...
Additional arguments (not used).
See also
t_test for the main analysis function.
Examples
result <- t_test(survey_data, life_satisfaction, group = gender)
summary(result)
#> t-Test Results
#> --------------
#>
#> - Grouping variable: gender
#> - Groups compared: Male vs. Female
#> - Confidence level: 95.0%
#> - Alternative hypothesis: two.sided
#> - Null hypothesis (mu): 0.000
#>
#> --- life_satisfaction ---
#>
#> Group Statistics:
#> ----------------------------------------------------
#> gender N Mean Std. Deviation Std. Error Mean
#> ----------------------------------------------------
#> Male 1149 3.603 1.165 0.034
#> Female 1272 3.651 1.142 0.032
#> ----------------------------------------------------
#>
#> Independent Samples Test:
#> --------------------------------------------------------------------------------------------------------
#> t df p Mean Diff. SE Diff. 95% CI Lower 95% CI Upper
#> --------------------------------------------------------------------------------------------------------
#> Equal variances assumed -1.019 2419 .308 -0.048 0.047 -0.140 0.044
#> Equal variances not assumed -1.018 2384.147 .309 -0.048 0.047 -0.140 0.044
#> --------------------------------------------------------------------------------------------------------
#>
#> Effect Sizes:
#> -----------------------------------------------------------------
#> Variable Cohen's d Hedges' g Glass' Delta Magnitude
#> -----------------------------------------------------------------
#> life_satisfaction -0.041 -0.041 -0.041 negligible
#> -----------------------------------------------------------------
#>
#> Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05
#>
#> Effect Size Interpretation:
#> - Cohen's d: pooled standard deviation (classic)
#> - Hedges' g: bias-corrected Cohen's d (preferred)
#> - Glass' Delta: control group standard deviation only
#> - Small effect: |effect| ~ 0.2
#> - Medium effect: |effect| ~ 0.5
#> - Large effect: |effect| ~ 0.8
summary(result, effect_sizes = FALSE)
#> t-Test Results
#> --------------
#>
#> - Grouping variable: gender
#> - Groups compared: Male vs. Female
#> - Confidence level: 95.0%
#> - Alternative hypothesis: two.sided
#> - Null hypothesis (mu): 0.000
#>
#> --- life_satisfaction ---
#>
#> Group Statistics:
#> ----------------------------------------------------
#> gender N Mean Std. Deviation Std. Error Mean
#> ----------------------------------------------------
#> Male 1149 3.603 1.165 0.034
#> Female 1272 3.651 1.142 0.032
#> ----------------------------------------------------
#>
#> Independent Samples Test:
#> --------------------------------------------------------------------------------------------------------
#> t df p Mean Diff. SE Diff. 95% CI Lower 95% CI Upper
#> --------------------------------------------------------------------------------------------------------
#> Equal variances assumed -1.019 2419 .308 -0.048 0.047 -0.140 0.044
#> Equal variances not assumed -1.018 2384.147 .309 -0.048 0.047 -0.140 0.044
#> --------------------------------------------------------------------------------------------------------
#>
#> Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05