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Create a heatmap showing issues with items

Source: R/ci_heatmap.R
ci_heatmap.Rd

When conducting cognitive interviews, it can be useful to quickly inspect the code distributions for each item. These heatmaps facilitate that process.

Usage

ci_heatmap(
  x,
  nrmSpec = NULL,
  language = nrmSpec$defaultLanguage,
  wrapLabels = 80,
  itemOrder = NULL,
  itemLabels = NULL,
  itemIdentifier = "uiid",
  codingScheme = "peterson",
  itemlab = NULL,
  codelab = NULL,
  freqlab = "Count",
  plotTitle = "Cognitive Interview Heatmap",
  fillScale = ggplot2::scale_fill_viridis_c(),
  theme = ggplot2::theme_minimal()
)

Arguments

x

The object with the parsed coded source(s) as resulting from a call to parse_source() or parse_sources().

nrmSpec

Optionally, an imported Narrative Response Model specification, as imported with ci_import_nrm_spec(), which will then be used to obtain the item labels.

language

If nrmSpec is specified, the language to use.

wrapLabels

Whether to wrap the labels; if not NULL, the number of character to wrap at.

itemOrder, itemLabels

Instead of specifying an NRM specification, you can also directly specify the item order and item labels. itemOrder is a character vector of item identifiers, and itemLabels is a named character vector of item labels, where each value's name is the corresponding item identifier. If itemLabels is provided but itemOrder is not, the order of the itemLabel is used.

itemIdentifier

The column identifying the items; the class instance identifier prefix, e.g. if item identifiers are specified as [[uiid:familySize_7djdy62d]], the itemIdentifier to pass here is "uiid".

codingScheme

The coding scheme, either as a string if it represents one of the cognitive interviewig coding schemes provided with the rock package, or as a coding scheme resulting from a call to create_codingScheme().

itemlab, codelab, freqlab

Labels to use for the item and code axes and for the frequency color legend (NULL to omit the label).

plotTitle

The title to use for the plot

fillScale

Convenient way to specify the fill scale (the colours)

theme

Convenient way to specify the ggplot2::ggplot() theme.

Value

The heatmap as a ggplot2 plot.

Examples

examplePath <- file.path(system.file(package="rock"), 'extdata');
parsedCI <- rock::parse_source(
  file.path(examplePath,
            "ci_example_1.rock")
);

rock::ci_heatmap(parsedCI,
                 codingScheme = "peterson");