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Create a custom analysis layer

group_analyze.Rd

Allows a user-defined function to compute summary statistics. The function receives a data subset and the target variable name for each group combination, and returns a data.frame of results.

Usage

group_analyze(
  target_var,
  by = NULL,
  where = NULL,
  analyze_fn,
  settings = layer_settings()
)

Arguments

target_var

Character string naming the target variable(s)

by

Character string or vector for row grouping

where

Expression for filtering data for this layer

analyze_fn

A function with signature function(.data, .target_var) that returns a data.frame. See Details.

settings

A layer_settings object

Value

A tplyr_analyze_layer object

Details

The analyze_fn is called once per group combination (defined by cols and by data variables). It receives:

  • .data: A data.frame subset for the current group

  • .target_var: Character string with the target variable name(s)

If format_strings are provided in settings, analyze_fn should return a single-row data.frame of named numeric values. Each format string entry becomes one output row, with its name used as the row label.

If no format_strings are provided, analyze_fn must return a data.frame with row_label and formatted columns.

Note that analyze_fn is called once per cols x by combination, so it only ever sees a single treatment column at a time — it cannot compute a statistic across the treatment columns. For an omnibus association test that spans the columns (e.g. Fisher's exact or CMH on a count/shift layer), see assoc_test.

See also

assoc_test for cross-column association tests.