A researcher designs an experiment by manipulating the following variables: temperature (low or high), illumination level (low o
r high), and time of testing (day or night). For a repeated measures design, how many participants would the researcher require in order to have 10 participants per condition?
As it could be inferred from the name, repeated measure design may be explained as experimental measures involving multiple (more than one) measures of a variable on the same observation, subject or participants which are taken at either various times or periodic intervals, different levels, different conditions. Hence, a repeated measurement taken with the same sample but under different treatment conditions. Therefore, since the measurement will be performed on a the same subjects(paired) , then the number of subjects needed will be 10. As it is this same samples that will be used for the other levels or conditions.
