PO218 Study Guide - Midterm Guide: Central Tendency, Cumulative Frequency Analysis, Collectively Exhaustive Events
Document Summary
Percentages and proportions supply a frame of reference for reporting research results in the sense that they standardize the raw data: Percentage (%): (f/n) x 100 where f=frequency, or the number of cases in any category n= the number of cases in all categories. Percentages and proportions can be calculated for variables at the ordinal and nominal levels of measurement, even though they require some division. When working with a small number of cases, it is preferable to report the actual frequencies rather than percentages or proportions. Ratios and rates provide additional ways of summarizing results. Ratios are useful for comparing categories of a variable in terms of relative frequency. Ratios are determined by dividing the frequency of one category by the frequency in another. Formula: fi f2 where fi= the number of cases in the irst category f2= the number of cases in the second category. Rates provide another way of summarizing the distribution of a single variable.
