3.3 Measures of Position

Question 1

Z-Score

Answer 1

The number of standard deviations a number is from the mean.

Question 2

First Quartile

Answer 2

Denoted Q₁, separates the lowest 25% of the data from the highest 75%.

Question 3

Second Quartile

Answer 3

Denoted Q₂, separates the lowest 50% of the data from the upper 50%. Same as the median.

Question 4

Third Quartile

Answer 4

Denoted Q₃, separates the lowest 75% of the data from the highest 25%.

Question 5

Percentile

Answer 5

Separates the lowest p% of the data from the highest (100-p)%.

Question 6

Five-Number Summary

Answer 6

Consists of the following quantiles:

1. Minimum
2. First Quartile
3. Median
4. Third Quartile
5. Maximum

Question 7

Interquartile Range

Answer 7

Found by subtracting the first quartile from the third quartile.

IQR = Q₃ - Q₁

Question 8

IQR Method

Answer 8

1. Find the first quartile and the third quartile
2. Compute the interquartile range
3. Compute the outlier boundaries (lower and upper)
4. Identify the outliers.

Question 9

Boxplot

Answer 9

A graph that presentas the five number summary along with some additional information about a data set.

Question 10

Measures of Position

Answer 10

Compare a data value to others in the data set.

Question 11

Outlier Boundary

Answer 11

The cutoff points for determining outliers.

Question 12

Lower Outlier Boundary

Answer 12

Q₁ - 1.5 * IQR

Question 13

Upper Outlier Boundary

Answer 13

Q₃​ + 1.5 * IQR