Chapter 4

Question 1

Z-score

Answer 1

z-score tells us the number of standard deviations a particular measurement is from the mean

Question 2

The Empirical Rule

Answer 2

Property 1: 68.26% of all possible observations lie within one standard deviation on either side of the mean.
Property 2: 95.44% of all possible observations lie within two standard deviations on either side of the mean.
Property 3: 99.74% of all possible observations lie within three standard deviations on either side of the mean.

Question 3

Shifting Data

Answer 3

Results in shifting (increasing or decreasing) the measures of position (mean, median, quartiles, minimum and maximum)
* Spread and shape do not change.

Question 4

Rescaling Data

Answer 4

multiplying (or dividing) by a constant (for each data value)
* Results in all measures of position (mean, median, quartiles, minimum and maximum) being
multiplied by the same constant.
* AND, all measures of spread (standard deviation and IQR) being multiplied by the same
constant.
* Shape does not change.