Measures of Center
What is the mode in the set {4, 5, 5, 7, 9, 9}?
In a normal distribution, where are the mean, median, and mean located?
They are all in the middle of the curve.
Variation
Given the set [1, 9, 2, 15], calculate Q2.
5.5
Given a mean of 35 and st dev of 2.1. What is the z-score of a data point of 39?
1.9
What is the median in the set {4, 5, 5, 7, 9, 9}?
Median is 6
Would you expect the average age of people learning to ride a bike to be left or right skewed?
Right skewed.
Given the set [1, 9, 2, 15], calculate the MAD.
5.25
Given the set [1, 2, 6, 7, 8, 15], calculate Q1
2
Given a mean of 35 and st dev of 2.1. What is the z-score of a data point of 29?
-2.88
What is the mean of the set {4, 5, 5, 7, 9, 9}?
Mean is 6.5
In a graph that shows left skew, which side will the long tail lie?
Left skew has tail on the left.
Given the set [1, 9, 2, 15], calculate the st dev.
6.55
Given the set [1, 2, 6, 8, 10, 11, 12, 16, 17], calculate Q3
14
What percentage of data lies between -2 and 1 standard deviations?
34+34+13.5=81.5%
Range is 24
Where would you find the mode in a graph that is left skewed?
To the right of the median.
Given the set [2, 5, 7, 8, 9, 10, 11], calc the MAD (round to TWO decimal places)
2.37
Given the set [1, 2, 6, 8, 10, 11, 12, 16, 17], calculate the IQR
10
Given the data set [2, 5, 8, 10, 12, 17, 21], determine the 75th percentile of the data.
position 6, which is 17!
Of the mean, median, and range, which is affected by adding or subtracting a constant from each term in the set?
Mean and median would change
Where would you find the mean in a graph that is right skewed?
To the right of the median.
Given the set [11, 15, 19, 20, 21, 22, 23, 30], calculate the st dev. (round to two decimals)
99.88
Given the set [2, 4, 6, 8, 10, 20], determine the upper fence and if any outliers.
UF=19, outlier is 20
Given the data set [2, 5, 8, 10, 12, 17, 21], determine the 60th percentile of the data.
Position 4.8, which is between 10 and 12, specifically 11.6