Standard Deviation Measure of Spread

What does this symbol represent?

• Standard Deviation

• Variance

• Mean Absolute Deviation

• Sigma

Which of the following is a measure of spread, or variability? (select all that apply)

• Interquartile Range

• Standard Deviation

• Mean

• Median

• Range

What does a standard deviation of 0 mean?

• There is no spread of data

• The spread of data is close to the mean

• The data is more spread out from the mean

• There is no mean

Ervin bowled 7 games last weekend. His scores are: 155, 165, 138, 172, 127, 193, 142. What is the sample standard deviation of Ervin's scores?

• 511.33

• 22.61

• 438.48

• 20.94

According to the picture, what is the standard deviation of the data set?

• 6.3

• 44

• 3.6

• 3.3

All of the below sets have the same mean.
Set 1-Standard Deviation=3.1
Set 2-Standard Deviation=4.9
Set 3-Standard Deviation=1.7
Set 4-Standard Deviation=3.2
Which set of data probably has the points closest to the mean?

• 1

• 2

• 3

• 4

Which set of data probably has the points furthest to the mean?

• 1

• 2

• 3

• 4

Sylvia believes that the students in Term 2 had a higher average number of minutes of exercise than Term 1 because the IQR and Standard Deviation is higher for that group of students. Do you agree?

• Sylvia is correct. Since the standard deviation and IQR for Term 2 students is higher, this means that students spent more time exercising, on average, than Term 1.

• Sylvia is incorrect. The standard deviation and the IQR shows that there is greater variability in the amount of time exercising for Term 2 students compared to Term 1, but it does not tell us that the group spent more time exercising than Term 1.

The table on the right shows the statistics for the number of hours of homework per night during Term 1 and Term 2 for a group of students. What must be true?

• Term 1 students spent less time on homework than Term 2, but there was more variation in the number of hours spent on the homework.

• Term 2 students spent less time on homework than Term 1, but there was more variation in the number of hours spent on the homework.

• Term 1 students spent less time on homework than Term 2, but there was less variation in the number of hours spent on the homework.

• Term 2 students spent less time on homework than Term 1, but there was less variation in the number of hours spent on the homework.

The chart on the left shows the statistics on test scores in period 1 and period 5. Which is true?

• The average test score is higher for period 5, but the data is more spread out.

• The average test score is higher for period 1, but the data is more spread out.

• The average test score is higher for period 5, and the data is more consistent (closer to the mean) than period 1.

• The average test score is higher for period 1, and the data is more consistent (closer to the mean) than period 5.