Lecture 4: Central Tendency

central tendency

similarity of values within a distribution (group)

mean

average

mode

most frequently occurring value

median

the central value of a distribution (50% above/below)

median-split

used to turn a continuous variable into a discrete (dichotomous) variable; not a measure of central tendency

what does a median split do?

determines the median and separates values into 2 groups (hi, low)

central limit theorem (bell shaped curve)

cases converge toward the center of a distribution of values; more cases means the greater the central tendency

normal

symmetric

negatively (left) skewed

tail and mean to the left

positively (right) skewed

tail and mean to the right