Section 3.2

mode

a variable is the most frequent observation of the variable that occurs in the data set

median

a variable is the value that lies in the middle of the data when arranged in ascending order. We use M to represent the median.

resistant

if extreme values (very large or small) relative to the data do not affect its value substantially.

Medium data

is best used for when the data are skewed to the right and the median is better for skewed data

population arithmetic mean

is computed using all the individuals in a population. aka population mean is a parameter. is denoted by μ symbol

sample arithmetic mean

is computed using sample data. aka statistic. denoted by _ x

arithmetic mean

of a variable is computed by determining the sum of all the values of the variable in the data set divided by the number of observations

Mean tendencies

when data is skewed the mean is usually pulled in the direction of the tail. The oberserv tend to increase the mean

comment on the role that the number of observations plays in restistance

...as the sample size increases the impact of the misrecored data on the mean increases

to find price mean

154/53=2.9 remember to round

no mode.

If there is no observation that occurs with the most frequency