#### Question

# Statistics help please?

1. The standard deviation and variance are measures of:

a. The general location of a set of scores.

b. How spread out the scores in a set of a set of data are from one another.

c. Both of the above

d. None of the above

2. Which of the following sets of scores has the largest amount of variability?

a. 102.7, 103.2, 104.6, 103.5, 100.9, 101.4

b. 11, 12, 12, 12, 12, 12, 12, 13

c. 1, 0, 6, 9, 12, 14, 3, 8, 17, 2, 5, 6, 15

d. 1,000,000; 1,000,001; 1,000,002, 1,000,004

3. If you score below average on a midterm exam, you're more likely to get a higher letter grade if the standard deviation is:

a. Small

b. Medium

c. Large

d. Cannot be determined from the information given

4. A researcher who is interested in introversion-extroversion wants to study the entire range of behavior from extremely introverted to extremely extroverted. The researcher needs a group of subjects for whom the variability of introversion-extroversion is

a. Small

b. Medium

c. Large

d. None of these

6. When computing the variance or standard deviation, all of the deviations from the mean are squared. The squaring provides the following advantage:

a. When we add the deviation, it prevents the result from always being zero.

b. Returns the outcome to the original scale of measurement.

c. Yields a more accurate estimate of the population

d. All of the above

7. When computing the standard deviation, the last step is to take the square root of the variance, this is done to:

a. Prevent the result from always being zero

b. Return to the original scale of measurement

c. Yield a more accurate estimate of the population

d. All of the above

8. A teacher wishes to compute the standard deviation of a midterm exam. The teacher is interested in only this class and does not wish to draw conclusions about any population. Before taking the square root, the sum of squares should be devided by:

a. N

b. N-1

c. N-2

d. None of these

11. If a sample variance is computed by dividing the SS by df= n-1, then the average value of the sample variances from all possible random samples of the size n will be ___ the population variance

a. Smaller than

b. Larger than

c. Exactly equal to

d. Unrelated to

12. For a particular sample, the largest distance (deviation) between a score and the mean is 11 points. The smallest distance between a score and the mean is 4 points. Therefore the deviation ____ .

a. Will be less than 4

b. Will be between 11 and 4

c. Will be greater than 11

d. It is impossible to say anything about the deviation without more information

13. The smallest score in a population is x=5 and the largest score is x=10. Based on this information you can conclude that

a. The population mean is somewhere between 5 and 10

b. The population standard deviation is smaller than 6

c. Both of these

d. Neither of these

14. If the variability of a set of scores is small

a. Many of the scores have large deviations from the mean

b. Most of the scores will be close to the mean

c. The sum of deviations from the mean will be large

d. The sum of the deviations from the mean will be between 0.01 and 0.05

#### Answers

1. The standard deviation and variance are measures of:

b. How spread out the scores in a set of a set of data are from one another.

2. Which of the following sets of scores has the largest amount of variability?

c. 1, 0, 6, 9, 12, 14, 3, 8, 17, 2, 5, 6, 15

3. If you score below average on a midterm exam, you're more likely to get a higher letter grade if the standard deviation is:

a. Small

4. A researcher who is interested in introversion-extroversion wants to study the entire range of behavior from extremely introverted to extremely extroverted. The researcher needs a group of subjects for whom the variability of introversion-extroversion is

c. Large

6. When computing the variance or standard deviation, all of the deviations from the mean are squared. The squaring provides the following advantage:

a. When we add the deviation, it prevents the result from always being zero.

7. When computing the standard deviation, the last step is to take the square root of the variance, this is done to:

a. Prevent the result from always being zero

8. A teacher wishes to compute the standard deviation of a midterm exam. The teacher is interested in only this class and does not wish to draw conclusions about any population. Before taking the square root, the sum of squares should be devided by:

b. N-1

11. If a sample variance is computed by dividing the SS by df= n-1, then the average value of the sample variances from all possible random samples of the size n will be ___ the population variance

b. Larger than

12. For a particular sample, the largest distance (deviation) between a score and the mean is 11 points. The smallest distance between a score and the mean is 4 points. Therefore the deviation ____ .

b. Will be between 11 and 4

13. The smallest score in a population is x=5 and the largest score is x=10. Based on this information you can conclude that

c. Both of these

14. If the variability of a set of scores is small

b. Most of the scores will be close to the mean