analyze_time_bins {eyetrackingR}

analyze_time_bins()

Description

Runs a test on each time-bin of time_sequence_data. Supports t.test, wilcox.test, (g)lm, and (g)lmer. Also includes support for the "bootstrapped-splines" test (see ?make_boot_splines_data and the divergence vignette for more info). By default, this function uses 'proportion-looking' (Prop) as the DV, which can be changed by manually specifying the formula. Results can be plotted to see how test-results or parameters estimates vary over time. P-values can be adjusted for multiple comparisons with p_adjust_method.

Usage

analyze_time_bins(data, ...)

## S3 method for class 'time_sequence_data'
analyze_time_bins(
  data,
  predictor_column,
  test,
  threshold = NULL,
  alpha = NULL,
  aoi = NULL,
  formula = NULL,
  treatment_level = NULL,
  p_adjust_method = "none",
  quiet = FALSE,
  ...
)

Arguments

data

The output of the 'make_time_sequence_data' function

...

Any other arguments to be passed to the selected 'test' function (e.g., paired, var.equal, etc.)

predictor_column

The variable whose test statistic you are interested in. If you are not interested in a predictor, but the intercept, you can enter "intercept" for this argument. Interaction terms are not currently supported.

test

What type of test should be performed in each time bin? Supports t.test, wilcox.test, (g)lm, and (g)lmer. Also includes support for the "bootstrapped-splines" test (see ?make_boot_splines_data and the divergence vignette for more info).

threshold

Value of statistic used in determining significance

alpha

Alpha value for determining significance, ignored if threshold is given

aoi

Which AOI should be analyzed? If not specified (and dataframe has multiple AOIs), then AOI should be a predictor/covariate in your model (so 'formula' needs to be specified).

formula

What formula should be used for the test? Optional for all but (g)lmer, if unset will use Prop ~ [predictor_column]. Change this if you want to use a custom DV.

treatment_level

If your predictor is a factor, regression functions like 'lm' and 'lmer' by default will treatment-code it. One option is to sum-code this predictor yourself before entering it into this function. Another is to use the 'treatment_level' argument, which specifies the level of the predictor. For example, you are testing a model where 'Target' is a predictor, which has two levels, 'Animate' and 'Inanimate'. R will code 'Animate' as the reference level, and code 'Inanimate' as the treatment level. You'd therefore want to set 'treatment_level = Inanimate'.

p_adjust_method

Method to adjust p.values for multiple corrections (default="none"). See p.adjust.methods.

quiet

Should messages and progress bars be suppressed? Default is to show

Value

A dataframe indicating the results of the test at each time-bin.

Methods (by class)

• analyze_time_bins(time_sequence_data):

Examples

## Not run: 
data(word_recognition)
data <- make_eyetrackingr_data(word_recognition,
                               participant_column = "ParticipantName",
                               trial_column = "Trial",
                               time_column = "TimeFromTrialOnset",
                               trackloss_column = "TrackLoss",
                               aoi_columns = c('Animate','Inanimate'),
                               treat_non_aoi_looks_as_missing = TRUE
)
response_time <- make_time_sequence_data(data, time_bin_size = 250,
                                         predictor_columns = c("MCDI_Total"),
                                         aois = "Animate", summarize_by = "ParticipantName")
tb_analysis <- analyze_time_bins(response_time, predictor_column = "MCDI_Total",
                                 test = "lm", threshold = 2)
summary(tb_analysis)

## End(Not run)