Template for expressions with statistical details — add_expression

Creates an expression from a data frame containing statistical details. Ideally, this data frame would come from having run tidy_model_parameters() on your model object.

This function is currently not stable and should not be used outside of this package context.

Usage

add_expression_col(
  data,
  paired = FALSE,
  statistic.text = NULL,
  effsize.text = NULL,
  prior.type = NULL,
  n = NULL,
  n.text = ifelse(paired, list(quote(italic("n")["pairs"])),
    list(quote(italic("n")["obs"]))),
  digits = 2L,
  digits.df = 0L,
  digits.df.error = digits.df,
  ...
)

Arguments

data

A data frame containing details from the statistical analysis and should contain some or all of the the following columns:

statistic: the numeric value of a statistic.
df.error: the numeric value of a parameter being modeled (often degrees of freedom for the test); irrelevant. if there are no degrees of freedom.
df: relevant if the statistic in question has two degrees of freedom.
p.value: the two-sided p-value associated with observed statistic.
method: method describing the test carried out.
effectsize: name of the effect size (if not present, same as method).
estimate: estimated value of the effect size.
conf.level: width for the confidence intervals.
conf.low: lower bound for effect size estimate.
conf.high: upper bound for effect size estimate.
bf10: Bayes Factor value (if bayesian = TRUE).

paired

Logical that decides whether the experimental design is repeated measures/within-subjects or between-subjects. The default is FALSE.

statistic.text

A character that specifies the relevant test statistic. For example, for tests with t-statistic, statistic.text = "t".

effsize.text

A character that specifies the relevant effect size.

prior.type

The type of prior.

n

An integer specifying the sample size used for the test.

n.text

A character that specifies the design, which will determine what the n stands for. It defaults to quote(italic("n")["pairs"]) if paired = TRUE, and to quote(italic("n")["obs"]) if paired = FALSE. If you wish to customize this further, you will need to provide object of language type.

digits, digits.df, digits.df.error

Number of decimal places to display for the parameters (default: 0L).

...

Currently ignored.

Citation

Patil, I., (2021). statsExpressions: R Package for Tidy Dataframes and Expressions with Statistical Details. Journal of Open Source Software, 6(61), 3236, https://doi.org/10.21105/joss.03236

Examples

set.seed(123)

# creating a data frame with stats results
stats_df <- cbind.data.frame(
  statistic  = 5.494,
  df         = 29.234,
  p.value    = 0.00001,
  estimate   = -1.980,
  conf.level = 0.95,
  conf.low   = -2.873,
  conf.high  = -1.088,
  method     = "Student's t-test"
)

# expression for *t*-statistic with Cohen's *d* as effect size
# note that the plotmath expressions need to be quoted
add_expression_col(
  data           = stats_df,
  statistic.text = list(quote(italic("t"))),
  effsize.text   = list(quote(italic("d"))),
  n              = 32L,
  n.text         = list(quote(italic("n")["no.obs"])),
  digits         = 3L,
  digits.df      = 3L
)
#> # A tibble: 1 × 11
#>   statistic    df p.value effectsize       estimate conf.level conf.low
#>       <dbl> <dbl>   <dbl> <chr>               <dbl>      <dbl>    <dbl>
#> 1      5.49  29.2 0.00001 Student's t-test    -1.98       0.95    -2.87
#>   conf.high method           n.obs expression
#>       <dbl> <chr>            <int> <list>    
#> 1     -1.09 Student's t-test    32 <language>