freqavg {equate} | R Documentation |
This function replaces frequencies falling below a specified threshold with an average of adjacent values. Frequency averaging is a simple method for smoothing a score distribution, typically one with unobserved scores (for a description see Moses & Holland, 2008).
freqavg(x, jmin = 1)
x |
two-column matrix of class “freqtab ”, where column 1 specifies the score scale and column 2 the frequencies for each score point
|
jmin |
the minimum frequency, as an integer, below which frequencies will be replaced |
Returns a vector of adjusted frequencies. If no values fall below jmin
these will simply be the original frequencies.
Anthony Albano tony.d.albano@gmail.com
Moses, T., & Holland, P. (2008). Notes on a general framework for observed score equating (ETS Research Rep. No. RR-08-59). Princeton, NJ: ETS.
set.seed(2005) x <- round(rnorm(1000,100,10)) xscale <- 70:130 xtab <- freqtab(x,xscale) # compare freqavg to freqbump: xavg <- freqavg(xtab) xbump <- freqbump(xtab[,2],Kx=60) cbind(xtab,avg=xavg,bump=round(xbump*sum(xtab[,2]),6))