Interpret Standard Deviation

Joanne's score on a test gives her a Z-score is -1.50. What does this mean?

• Joanne didn't take the test yet.

• Joanne's test score is 1.50 standard deviations below the average test score.

• Joanne did better than 1.50 times her peers.

• Joanne's test score, on average, was 1.5 points lower than the other test scores.

A data point has a z-score of -2.50. How should be interpret this information?

• This data point is 2.5 standard deviations above the mean

• This data point is 2.5 standard deviations above the median

• This data point is 2.5 standard deviations below the mean

• This data point is 2.5 standard deviations below the median

Answer explanation

A z-score of -2.50 indicates that the data point is 2.5 standard deviations below the mean. This means it is significantly lower than the average value.

Use the image of the normal graph provided. What is the value of the standard deviation?

• 6

• 12

• 36

• 18

On average, a randomly selected baby's apgar score will differ from the mean 8.128 by about 1.4 units.
This represent what?

• Interpret Standard deviation

• Interpret r

• Interpret r^2

• Interpret LSRL "yhat"

If two datasets have the same mean but different standard deviations, what does this tell us?

• They have the same data points

• They have data points spread out in the same way

• One has data points more spread out than the other

• They cannot be compared

What does standard deviation represent?

• How many different variations are in the data set.

• How the population varies compared to the sample.

• How spread out each data value is from the mean.

• How often the most popular choices in a sample were picked compared to the least popular choices

When comparing data sets, a higher Standard Deviation indicates...

• More consistency and less variability

• Less consistency and less variability

• More consistency and more variability

• Less consistency and more variability

Which best describes the shaded part of this normal distribution graph?

• All data that is one or higher.

• All data that is one or more standard deviations above the mean.

• All data that is between 1 and 3.

• All data that is above the mean.

What is the standard deviation on this Normal Curve?

• 6

• 12

• 34

• 18

What does the standard deviation tell us about the data set?

• How spread out the numbers are

• How much each number in the data set increases by

• How much each number in the data set decreases by