Question

1. If the standard deviation equals 0, we may conclude that:

a. There is no dispersion in the data

b. The mean is a good measure of the average

c. The data are homogeneous

d. Everyone scored the same

e. All of the above are correct

2. Distribution A and B have the same mean and range. The standard deviation of Distribution A is 30, and of Distribution B is 15. We may conclude that:

a. The scores in Distribution B are grouped closer to the mean than are the scores in Distribution A.

b. The scores in Distribution A are grouped closer to the mean than the scores in Distribution B.

c. There are twice as many scores from -1 standard deviation to +1 standard deviation in Distribution A

d. There are half as many scores from -1 standard deviation to +1 standard deviation in Distribution A.

e. Distribution A has at least one lower and one higher score than Distribution B

3. In a given distribution the mean = 80, standard deviation = 10. If three scores are added, namely, 70, 80, and 90, then this addition of data will cause the standard deviation to

a. Decrease in value

b. Increase in value

c. Remain the same

d. Unable to determine

4. On a statistics examination, an instructor finds that the standard deviation = 20.0 in an undergraduate class and 10.0 in a graduate seminar. Both groups have the same number of students. Which of the following statements is warranted?

a. Undergraduates performed better than graduate students

b. The distribution of the undergraduate students is normal

c. The performance of undergraduates is more variable than graduate students

d. The average performance for undergraduates is higher than for graduates

e. Cannot say unless we know the means

5. You obtain a score of 80 on a test. Which class would you rather be in?

a. Mean = 60, standard deviation = 20

b. Mean = 70, standard deviation = 15

c. Mean = 70, standard deviation = 10

d. Mean = 80, standard deviation = 2

e. Mean = 70, standard deviation = 2

6. The College of Arts and Science at Delta University has several departments. The number of faculty in each department is shown below. What is the MEDIAN number of faculty in each department in the College of Arts and Science? 8, 16, 10, 14, 8, 18, 12, 10, 6, 18

a. 12

b. 10

c. 11

d. 10.5

e. There is no median in this data

7. The College of Arts and Science at Delta University has several departments. The number of faculty in each department is shown below. What is the MEAN number of faculty in each department in the College of Arts and Science? 8, 16, 10, 14, 8, 18, 12, 10, 6, 18

a. 10

b. 10.5

c. 11

d. 12

e. There is no mean in this data

8. A graph that shows how often each value in a distribution was observed is called a

a. x-y graph

b. frequency distribution

c. measure of dispersion

d. variance

9. An example of an ordinal scale is

a. The numbers on basketball players jerseys

b. The weight of students in this class

c. The number of students in each program in CER

d. The ranking of basketball teams for March Madness

e. The temperature in degrees Fahrenheit

10. The salaries of employees at your company were given as $30,000; $50,000; $55,000; $20,000; $60,000; and $250,000, the measure of central tendency that best explains how much money your employees make is

a. Mean

b. Median

c. Mode

d. Variance

11. You stand at the door of a high school and survey the students entering about their attitudes toward adminstrators. This type of sampling is called

a. Simple random sampling

b. Convenience sampling

c. Cluster sampling

d. Probability sampling

12. A problem with gathering data at a door of a college dorm is

a. Only a certain type or types of students might use that door, e.g. freshman

b. All the disabled students might use that door since it has handicapped access

c. You may not get enough students to have a good sample size

d. All of the above

13. When you have a sample whose frequency distribution looks basically like a normal curve, you know that

a. There is no way to determine what percentage of the population would fall in each section

b. Its highest point is in the middle, showing that most people are “average.”

c. It is not symmetrical

d. You can only use very limited and complicated statistics to analyze your data

Answer 1

1. If the standard deviation equals 0, we may conclude that:

e. All of the above are correct

2. Distribution A and B have the same mean and range. The standard deviation of Distribution A is 30, and of Distribution B is 15. We may conclude that:

Same mean and range implies lowest and one highest score of A and B are same. Since the standard deviation of Distribution A is greater than that of B,

a. The scores in Distribution B are grouped closer to the mean than are the scores in Distribution A.

3. In a given distribution the mean = 80, standard deviation = 10. If three scores are added, namely, 70, 80, and 90, then this addition of data will cause the standard deviation to

d. Unable to determine

We need the initial number of scores.

4. On a statistics examination, an instructor finds that the standard deviation = 20.0 in an undergraduate class and 10.0 in a graduate seminar. Both groups have the same number of students. Which of the following statements is warranted?

c. The performance of undergraduates is more variable than graduate students

Because the standard deviation in an undergraduate class is greater than in graduate seminar.

5. You obtain a score of 80 on a test. Which class would you rather be in?

e. Mean = 70, standard deviation = 2

We need to be in a class for which z score is maximum.

z = (80 - 60) / 20 = 1

z = (80 - 70) / 15 = 0.67

z = (80 - 70) / 10 = 1

z = (80 - 80) / 2 = 0

z = (80 - 70) / 2 = 5

6. The College of Arts and Science at Delta University has several departments. The number of faculty in each department is shown below. What is the MEDIAN number of faculty in each department in the College of Arts and Science? 8, 16, 10, 14, 8, 18, 12, 10, 6, 18

c. 11

The data in sorted order is  6 8 8 10 10 12 14 16 18 18.

Median = average of middle elements = (10 + 12) / 2= 11

7. The College of Arts and Science at Delta University has several departments. The number of faculty in each department is shown below. What is the MEAN number of faculty in each department in the College of Arts and Science? 8, 16, 10, 14, 8, 18, 12, 10, 6, 18

d. 12

Mean = (8 +16+ 10+ 14+8 +18 + 12+ 10+ 6+ 18) / 10 = 12

8. A graph that shows how often each value in a distribution was observed is called a

b. frequency distribution

9. An example of an ordinal scale is

d. The ranking of basketball teams for March Madness

Because all others are nominal, interval or ratio scale

10. The salaries of employees at your company were given as $30,000; $50,000; $55,000; $20,000; $60,000; and $250,000, the measure of central tendency that best explains how much money your employees make is

b. Median

Because the value $250,000 makes the distribution skewed to the right.

11. You stand at the door of a high school and survey the students entering about their attitudes toward adminstrators. This type of sampling is called

b. Convenience sampling

12. A problem with gathering data at a door of a college dorm is

d. All of the above

13. When you have a sample whose frequency distribution looks basically like a normal curve, you know that

b. Its highest point is in the middle, showing that most people are “average.”