June13class

Minimum Rules for Frequency Tables
 * 1) same size intervals
 * 2) continuous intervals
 * 3) highest scores on top
 * 4) 10-12 intervals [others say 6 - 8]
 * 5) Odd interval scale - so that the mean can be determined easier
 * 6) lower score limit should be a mulitiple of the interval size, ex. interval set 3 then lower score set 21.

Steps for constructing Frequency tables
 * 1) determine lowest & highest score
 * 2) find range (highest score - lowest score)
 * 3) divide range by 10 & 20 (or 6 & 8) to determine acceptable widths
 * 4) determine lowest class interval
 * 5) list all intervals from lowest to highest
 * 6) count each score into its interval - these are absolute frequencies

For Excel 1. Highlight all the cells containing data - hit f2 key, then control shift enter

Percentile Rank % of cases that fall below a given score OR the score below which % of cases fall