fhch2010 {afex} | R Documentation

## Data from Freeman, Heathcote, Chalmers, & Hockley (2010)

### Description

Lexical decision and word naming latencies for 300 words and 300 nonwords presented in Freeman, Heathcote, Chalmers, and Hockley (2010). The study had one between-subjects factors, `"task"` with two levels (`"naming"` or `"lexdec"`), and four within-subjects factors: `"stimulus"` type with two levels (`"word"` or `"nonword"`), word `"density"` and word `"frequency"` each with two levels (`"low"` and `"high"`) and stimulus `"length"` with three levels (4, 5, and 6).

### Usage

    fhch2010

### Format

A `data.frame` with 13,222 obs. of 9 variables:

id

  participant id, `factor`

task

  `factor` with two levels indicating which task was performed: `"naming"` or `"lexdec"`

stimulus

  `factor` indicating whether the shown stimulus was a `"word"` or `"nonword"`

density

  `factor` indicating the neighborhood density of presented items with two levels: `"low"` and `"high"`. Density is defined as the number of words that differ from a base word by one letter or phoneme.

frequency

  `factor` indicating the word frequency of presented items with two levels: `"low"` (i.e., words that occur less often in natural language) and `"high"` (i.e., words that occur more often in natural language).

length

  `factor` with 3 levels (4, 5, or 6) indicating the number of characters of presented stimuli.

item

  `factor` with 600 levels: 300 words and 300 nonwords

rt

  response time in seconds

log_rt

  natural logarithm of response time in seconds

correct

  boolean indicating whether or not the response in the lexical decision task was correct or incorrect (incorrect responses of the naming task are not part of the data).

### Details

In the lexical-decision condition (N = 25), subjects indicated whether each item was a word or a nonword, by pressing either the left (labeled word) or right (labeled nonword) outermost button on a 6-button response pad. The next study item appeared immediately after the lexical decision response was given. In the naming condition (N = 20), subjects were asked to name each item aloud, and items remained on screen for 3 s. Naming time was recorded by a voice key.

Items consisted of 300 words, 75 in each set making up a factorial combination of high and low density and frequency, and 300 nonwords, with equal numbers of 4, 5, and 6 letter items in each set.

### Source

Freeman, E., Heathcote, A., Chalmers, K., & Hockley, W. (2010). Item effects in recognition memory for words. Journal of Memory and Language, 62(1), 1-18. http://doi.org/10.1016/j.jml.2009.09.004

### Examples

    data("fhch2010")
    str(fhch2010)

    a1 <- aov_ez("id", "log_rt", fhch2010, between = "task",
                 within = c("density", "frequency", "length", "stimulus"))
    nice(a1)

    lsmip(a1, frequency~length|task+stimulus)

    lsmip(a1, frequency~density|task+stimulus)

    ## Not run:
    a2 <- aov_ez("id", "rt", fhch2010, between = "task",
                 within = c("density", "frequency", "length", "stimulus"))
    nice(a2)

    lsmip(a2, frequency~length|task+stimulus)

    lsmip(a2, frequency~density|task+stimulus)

    ## End(Not run)

[Package afex version 0.18-0 Index]