Rating Scales - Measures of Central Tendency and Sample Sizes

摘要

The measurement of people's preferences has often been accomplished by the use of rating scales. For example, in much of the work investigating the change in visual amenity resulting from the reconstruction of roads, people's preferences for scenes were measured using a 'pleasantness' rating scale. This report considers two problems which arise from this rating procedure: (a) what reasons are there for deciding whether to use the mean or the median when a measure of central tendency is required and, (b) when a group measure of preference is required, what is the appropriate number of subjects to use (ie sample size). (Copyright (c) Crown Copyright 1981.)