the percentage of scores in a distribution that fall below a given score
mode
the most frequently occuring score in the distribution
mean
arithmetic average
median
the middle score
range
the diference between the highest and lowest scores in a distribution
standard deviation
the measure of score variability; computed by calculating the deviation of each score from the mean, squared it, finding the average and the square root of that
normal curve
bell shaped distribution
regression toward the mean
the tendency for extremes of unusuall scores to fall back toward the average
statistical significnance
a statistictical statement abotu how liekly it is that a result occured by chance
