Question

1. Among frequency distributions for physical stamina scores, the greatest variability probably would occur in the distribution for
   1. well‑trained athletes.
   2. patients at a health clinic.
   3. infants.
   4. the general population.

2. When calculating the variance, each deviation is squared in order to
   1. eliminate negative signs from deviation scores.
   2. generate squared units of measurement.
   3. emphasize the contributions of larger deviations.
   4. attain all of the above.

3. Five children are tested for IQ and their scores are: 110, 160, 100, 100, 110. What is the best way to describe the central tendency of these scores?
   1. the mode
   2. the median
   3. the mean
   4. the range

4. Knowing the standard deviation of a set of scores, it is possible to calculate
   1. range
   2. variance
   3. the mean
   4. the frequency distribution

5. When summarizing data, why is it important to report both the mean and the standard deviation?
   1. two sets of data could have the same mean but different amounts of variability
   2. this way both descriptive and inferential statistics are covered
   3. this way the null hypothesis can be evaluated
   4. this enables the researcher to avoid Type I and Type II errors

6. Indicate which one of the following sets of observations has the larger standard deviation. (Calculations aren't necessary to answer this question.)
   1. 4045, 4050, 4055
   2. 5, 20, 35
   3. 530, 540, 550
   4. 988, 1000, 1012

7. If the distribution of weekly study times reported by college students has a mean of 25 hours with a standard deviation of 10 hours, this implies that
   1. a small minority study either less than 5 hours or more than 45 hours.
   2. a majority study between 15 and 35 hours.
   3. individuals deviate, on the average, approximately 10 hours from the mean of 25 hours.
   4. all of the above

8. A key property of the interquartile range is its
   1. resistance to the distorting effect of extreme observations.   
   2. sensitivity to all observations.
   3. sensitivity to extreme observations.
   4. use of information from only two observations.

9. If the normal curve is used to describe the distribution of IQ scores for all currently enrolled students in U.S. colleges and universities, all students are identified with the
   1. smooth normal curve.
   2. total area under the normal curve.
   3. maximum height of the normal curve.
   4. horizontal axis.

10. Since the normal curve never actually touches the horizontal axis,
    1. most of the area is in its extremities.
    2. the total area is infinitely large.
    3. the normal tables are only approximate.
    4. very extreme observations are possible.           

11. Any particular normal curve is transformed into a new normal curve whenever changes occur in
    1. its mean.                   
    2. its standard deviation.          
    3. both its mean and its standard deviation.                   
    4. either its mean or its standard deviation.

12. For any z score, the corresponding proportions in columns B and C always sum to
    1. 1.0000
    2. 0.5000
    3. 0.0000
    4. the value of z.

13. If a positively skewed distribution of incomes is transformed into a distribution of z scores, the shape of the new distribution will be
    1. normal.
    2. positively skewed.
    3. intermediate between normal and positively skewed.
    4. standard normal.

14. Which of the following test scores would be the most preferable on a psychology exam?
    1. a score of 40 in a distribution with a mean of 35 and a standard deviation of 5
    2. a score of 36 in a distribution with a mean of 30 and a standard deviation of 4
    3. a score of 30 in a distribution with a mean of 24 and a standard deviation of 2
    4. a score of 25 in a distribution with a mean of 15 and a standard deviation of 4

15. Transformations from z scores to other types of standard scores
    1. change the shape of the original distribution, but not the relative standing of any test score within the distribution.
    2. change the relative standing of any test score within the original distribution, but not the shape of the distribution.
    3. change both the shape of the original distribution and the relative standing of any test score within the distribution.
    4. change neither the shape of the original distribution nor the relative standing of any test score within the distribution.

Answer 1

Among frequency distributions for physical stamina scores, the greatest variability probably would occur in the distribution for

Answer: d. the general population

When calculating the variance, each deviation is squared in order to

Answer: a. eliminate negative signs from deviation scores.

Five children are tested for IQ and their scores are: 110, 160, 100, 100, 110. What is the best way to describe the central tendency of these scores?

Answer: c. the mean

Knowing the standard deviation of a set of scores, it is possible to calculate

Answer: b. variance

When summarizing data, why is it important to report both the mean and the standard deviation?

Answer: a. two sets of data could have the same mean but different amounts of variability

Indicate which one of the following sets of observations has the larger standard deviation. (Calculations aren't necessary to answer this question.)

Answer: b. 5, 20, 35

If the distribution of weekly study times reported by college students has a mean of 25 hours with a standard deviation of 10 hours, this implies that

Answer: d. all of the above

A key property of the interquartile range is its

Answer: a. resistance to the distorting effect of extreme observations.  

If the normal curve is used to describe the distribution of IQ scores for all currently enrolled students in U.S. colleges and universities, all students are identified with the

Answer: b. total area under the normal curve.

Since the normal curve never actually touches the horizontal axis,

Answer: d. very extreme observations are possible.          

Any particular normal curve is transformed into a new normal curve whenever changes occur in

Answer: a. mean

For any z score, the corresponding proportions in columns B and C always sum to

Answer: Please provide the details of columns B and C to answer this question. I suspect that it should be a. 1.0000

If a positively skewed distribution of incomes is transformed into a distribution of z scores, the shape of the new distribution will be

Answer: d. standard normal

Which of the following test scores would be the most preferable on a psychology exam?

Answer: c. a score of 30 in a distribution with a mean of 24 and a standard deviation of 2

Transformations from z scores to other types of standard scores

c. change both the shape of the original distribution and the relative standing of any test score within the distribution.

Good luck with your studies!!!