Multiple choice questions

[Skip Breadcrumb Navigation]

Chapter 5: Standard deviation and z-scores: The standard unit of measurement in statistics

Try the multiple choice questions below to test your knowledge of this chapter. Once you have completed the test, click on 'Submit Answers for Grading' to get your results.

This activity contains 13 questions.

Which of the following is the best definition of standard deviation?

The average of a set of scores.The 'average' of the sum of squared deviations from the mean.The typical amount by which scores differ from the mean of a set of scores.The mean squared deviation from the average.

Which of the following is true?

Standard deviation is the square root of variance.Standard deviation is the square of the variance.Standard deviation is the 'average' variance.Standard deviation is variance divided by N - 1.

Which of the following is true?

Standard deviation is always greater than the variance.The standard deviation formula gives greater emphasis to scores at the mean.Standard deviation has few applications in statistics.Standard deviation always involves a particular unit of measurement such as kilograms.

A researcher obtains a standard deviation of -6.23 for the variable 'achievement motivation'.

There must be an error in the calculation.We would expect negative values as often as positive ones.The mean score must be 0.00 for this to happen.The researcher should square the value to get rid of the minus sign.

A z-score of -3.0 means:

that there is a mistake in your calculation.that the score is below the sample mean.that you have too few decimal places.that the mean is three standard deviations below the particular score.

The mean of a set of scores is 5.0, the variance is 4.00, the standard deviation is 2.0, and the mode is 3.5. What is a score of 8.00 expressed as a z-score?

-2.001.501.252.00

A researcher decides to measure mathematical ability by adding together the z-scores on 'addition' and 'multiplication'. The mean score on 'addition' is 20.00 and the standard deviation is 3.00; the mean score on multiplication is 5.00 and the standard deviation is 1.00. What would be the score on mathematical ability for a child who scored 26.00 on 'addition' and 8.00 on 'multiplication'?

-1.00Impossible to calculate with the available information.28.005.00

If for three individuals the obtained z-scores were 3.00; -2.00; and 1.64, what would be the proportion of individuals who scored higher than them according to the table of the standard normal z-distribution?

0.13%, 2.28%, and 2.5%3.00%, 2.00%, and 1.64%2.64%0.13%, 97.72%, and 5.00%

Approximately how many people would have scores LOWER than an individual with a z-score of 1.96?

98.04%2.5%97.5%Cannot calculate this unless the standard deviation is given.

A standard score is:

a z-score.the standard deviation of a particular score.a constant.the mean score.

The z-score of Jack's age is -2.00 and the z-score of Jill's age is 1.00. Approximately what percentage of people are older than Jack but younger than Jill?

95%5.00%82%3.00%

z-scores should only be used with:

frequency data.percentages.nominal data.none of these.

The following data are needed to answer this question:
The IQ scores of five children are 100, 102, 98, 97 and 103.
The z-score of an IQ of 100 is:

0.00-1.00.60.00%

The Submit Answers for Grading feature requires scripting to function. Your browser either does not support scripting or you have turned scripting off.

So, the Submit Answers for Grading button below will not work.

The following Submit Answers for Grading button is provided in its place and will clear your answers:
The Clear Answers and Start Over feature requires scripting to function. Your browser either does not support scripting or you have turned scripting off.

So, the Clear Answers and Start Over button below will not work.

The following Clear Answers button is provided in its place and will clear your answers:

Your browser either does not support scripting or you have turned scripting off. Because of this, the answer choices will NOT appear in a different order each time the page is loaded, though that is mentioned below. Note that you do not need this feature to use this site.

Answer choices in this exercise appear in a different order each time the page is loaded.

Multiple choice questions

Which of the following is the best definition of standard deviation?

Which of the following is true?

Which of the following is true?

A researcher obtains a standard deviation of -6.23 for the variable 'achievement motivation'.

A z-score of -3.0 means:

The mean of a set of scores is 5.0, the variance is 4.00, the standard deviation is 2.0, and the mode is 3.5. What is a score of 8.00 expressed as a z-score?

If for three individuals the obtained z-scores were 3.00; -2.00; and 1.64, what would be the proportion of individuals who scored higher than them according to the table of the standard normal z-distribution?

Approximately how many people would have scores LOWER than an individual with a z-score of 1.96?

A standard score is:

The z-score of Jack's age is -2.00 and the z-score of Jill's age is 1.00. Approximately what percentage of people are older than Jack but younger than Jill?

z-scores should only be used with:

The following data are needed to answer this question: The IQ scores of five children are 100, 102, 98, 97 and 103. The z-score of an IQ of 100 is:

The following data are needed to answer this question:
The IQ scores of five children are 100, 102, 98, 97 and 103.
The z-score of an IQ of 100 is: