Statistics for the Behavioral Sciences 3rd edition ; exam review 2 Exam Already Passed!!

Notion used to represent population and sample mean - sample size (n) and population size (N) mean - The sum of a set of scores divided by the total number of scores summed Median - The middle score in a data set that is listed in numberical order Mode - The value in a data set that occurs most often or most frequently. The weighted mean - The combined mean of two or more groups of scores in which the number of scores in each group is disproportionate or unequal when to use the mean to summarize data - -Normal distributions of data -Interval and ratio scale data When to use the median to summarize data - -Skewed distributions of data -ordinal scale data When to use the mode to summarize data - -Modal distributions of data -Nominal scale data Variability - a measure of the dispersion or spread of scores in a distribution and ranges from 0 - infinity. ***Can never be negative**** How the range is calculated - the difference between largest value (L) and smallest value (S)Sample Variance - a measure of variability for the average squared distance that scores in a sample deviate from the mean. it is computed when only a portion or sample of data is measured in a population