A history professor gives a quiz to his class and records

Question 1

5 out of 5 points

A history professor gives a quiz to his class and records the following scores:

13, 11, 11, 9, 12, 13, 16, 14, 11, 10, 8, 13, 20.

The mode(s) for this distribution is(are) _________.

.

11 and 13

Question 2

5 out of 5 points

A history professor gives a quiz to his class and records the following scores:

13, 11, 11, 9, 12, 13, 16, 14, 11, 10, 8, 13, 20.

The standard deviation for this distribution is _________. Assume sample scores.

Question 3

0 out of 5 points

The mean number of students in a classroom at school A is 32.5 and there are 25 classrooms. The mean number of students at school B is 29.6 in 12 classrooms. At school C the mean in each class is 15.3 for 10 classrooms. What is the mean number of students per classroom for all the schools combined?

Question 4

0 out of 5 points

If 10 points were added to each score in a distribution, which of the following will happen?

Question 5

0 out of 5 points

In calculating the standard deviation of a sample, we use _________ in the denominator.

Question 6

5 out of 5 points

What is the appropriate symbol for the population standard deviation?

Question 7

0 out of 5 points

In a certain statistics course, four exams were given. Each student’s grade was based on a weighted average of his exam scores. The first two tests had weights of 1, the third test had a weight of 2, and the final test had a weight of 3. The exam scores for one student are listed below.

The student’s overall average was _________.

Question 8

5 out of 5 points

equals _______ .

Question 9

0 out of 5 points

equals _______ .

Question 10

0 out of 5 points

If the distribution is symmetrical, which is the best measure of central tendency?

Question 11

5 out of 5 points

equals _______ .

Question 12

5 out of 5 points

Assume one has a set of 35 scores with = 100 and s = 9. If 5 scores, each equal to 100 were added to the distribution, what effect would this have on ?

Question 13

5 out of 5 points

A distribution has a mean of 78 and a median of 92. This distribution is _________.

Question 14

5 out of 5 points

A history professor gives a quiz to his class and records the following scores:

13, 11, 11, 9, 12, 13, 16, 14, 11, 10, 8, 13, 20.

The median for this distribution is _________.

Question 15

5 out of 5 points

In a negatively skewed distribution, the mean will generally be _______ the median.

Question 16

5 out of 5 points

An industrial psychologist observed 8 drill-press operators for one working day. She recorded the number of times each operator pressed the “faster” button instead of the “stop” button to determine whether the design of the control panel was contributing to the high rate of accidents in the plant. The resulting scores were as follows:

5, 2, 8, 2, 3, 2, 4, 12

The median for this distribution is _________.

Question 17

5 out of 5 points

If s = 12 for a set of 200 scores and 5 points were subtracted from each of the scores, the new value of the standard deviation would be _________.

Question 18

5 out of 5 points

Given the following set of scores

X: 10, 12, 6, 8, 9, 11, 13, 13, 5, 0, 1

What is the variance?

Question 19

0 out of 5 points

Consider a distribution with N = 100, = 50, and = 9875. If 10 new scores of 50 were added to the distribution, what would happen to the sum of squares?

Question 20

5 out of 5 points

An industrial psychologist observed 8 drill-press operators for one working day. She recorded the

number of times each operator pressed the “faster” button instead of the “stop” button to

determine whether the design of the control panel was contributing to the high rate of accidents in

the plant. The resulting scores were as follows:

5, 2, 8, 2, 3, 2, 4, 12

The standard deviation for this distribution is _________. Assume sample data.