Understanding Measures of Variance and Standard Deviation

What is the range of a data set?

• The middle value when the data set is ordered.

• The difference between the greatest and least values.

• The sum of all values in the data set.

• The average of all values in the data set.

How does removing an outlier affect the range of a data set?

• It doubles the range.

• It does not affect the range.

• It decreases the range.

• It increases the range.

What does the standard deviation measure?

• The most frequently occurring value.

• The difference between the highest and lowest values.

• The spread of data around the mean.

• The average value of a data set.

Which step is NOT part of calculating the standard deviation?

• Squaring the result of each subtraction.

• Multiplying all data points by the mean.

• Subtracting the mean from each data point.

• Adding all squared results together.

In the example calculation, what is the mean of the data set {1, 1, 3, 5, 5}?

• 2

• 3

• 4

• 5

Why might a candidate with a smaller range not be the best choice for a spelling bee?

• Their scores are too low.

• Their scores are too consistent.

• Their scores are too high.

• Their scores are not consistent.

What does a high standard deviation indicate about a data set?

• The data is closely clustered around the mean.

• The data has a low mean value.

• The data is spread out far from the mean.

• The data has a high mean value.

When should you use the mean and standard deviation together?

• When the data has outliers.

• When the data is symmetrical.

• When the data is skewed.

• When the data is categorical.

What does a low standard deviation suggest about the data?

• The data has a low range.

• The data has a high range.

• The data is spread out.

• The data is clustered around the mean.

If a data set is skewed left, which measure of center is more appropriate?

• Range

• Mean

• Mode

• Median