Chapter 3 review

What score would need added to the following data set in order to make it bimodal? TABLE a. 34 b. 20 c. 37 d. 36

D

Which of the following is not an appropriate definition of the mean? a. The middle of all of the scores once they are ordered from least to greatest b. The balance point for a distribution c. The sum of the scores divided by the number of scores d. The amount each individual receives when the total of the scores is split equally

A

If the median is removed from a data set, what can you determine about the new median? a. The new median is equal to the original median. b. The new median is less than the original median. c. The new median is greater than the original median. d. There is nothing you can determine about the new median without knowing the list of scores.

D

Which of the following would not be a reason for using the median to measure central tendency of a distribution? a. The data is measured on an ordinal scale. b. Some values are undetermined. c. There are a few extreme scores. d. The data is measured on a nominal scale.

D

A researcher collected data on the number of traffic violations received by individuals younger than 30 years of age. The frequency distribution table displays the results of the data collection. TABLE To the nearest tenth, calculate the mean, median, and mode. a. mean = 1.4, median = 1, mode = 0 b. mean = 1, median = 1.4, mode = 2 and 3 c. mean = 1.4, median = 1, mode = 2 and 3 d. mean = 1.4, median = 2, mode = 1

A

A teacher gave a quiz to her class of 30 students. However, she misplaced one of the quizzes. The teacher calculated the mean of the 29 quizzes to be μ= 68 points. At this point, the teacher found the missing quiz. On this quiz, the student scored 98 points. What is the mean for the class of all 30 students? a. 69 b. 83 c. 65.7 d. 68

A

The mean of a set of scores is μ= 125. If we remove the score 122 from the set, what will happen to the mean? a. The mean will increase. b. The mean will stay the same. c. The mean will decrease. d. It is impossible to know what will happen to the mean without knowing the individual scores.

A

Given the following set of sample scores, calculate the sample mean. 3,4,5,6,8,10 a. 6 b. 4 c. 3 d. 5

A

A scientist cannot read a data point in a list of weights of newborn babies. The report, however, notes that the median weight is 8.6. What is the missing weight? 7.6, 8.1, _____, 8.8, 8.8, 8.9 a. 8.1 b. 8.4 c. 8.6 d. 8.8

B

For a positively skewed distribution with a mode of X = 31 and a mean of 36, the median is most probably _________________. a. greater than 36 b. between 31 and 36 c. less than 31 d. equal to 36

B

A survey collected data on people's favorite type of movie. The following table lists the results. TABLE Which of the follow measures of central tendency can be found for this data set? a. mean b. median c. mode d. all of the above

C

In a symmetrical distribution, which of the following must be in the center? The mean The median The mode a. I only b. II only c. I and II only d. I, II, and III

C

For a given set of scores with N = 20, if there are 10 different modes, which of the following is true? a. The situation is impossible. b. The set contains 20 different scores, each of which has a frequency of 1. c. There is nothing that can be known about the data set without more information. d. The set contains 10 different scores, each of which has a frequency of 2.

D

A scientist is studying the drinking habits of rabbits. She collected the daily volumes of water consumed by the rabbits in the sample. The data had a mode of 19, a median of 17, and μ= 14. Which of the following is likely true? a. The data is positively skewed. b. The data is negatively skewed. c. The data is symmetrical. d. The data is bimodal.

B

Given the following frequency distribution table, if all scores are increased by 5, what will the new mean be? X . F 1 . 5 2 . 3 3 . 3 4 . 1 a. 2 b. 7 c. 1 d. 10

B

In the following data set, removing which score leaves the mean and the median unchanged? 1, 1, 2, 2, 2, 4 a. 1 b. 2 c. 4 d. It is impossible to remove a score without affecting the median and the mean.

B

What is a valid reason why the mode is the only appropriate measure of central tendency to use with data measured on a nominal scale? a. In a nominal scale there are often undetermined values. b. In a nominal scale the categories are not numbers on which calculations can be performed. c. In a nominal scale there is the risk of extreme scores. d. In a nominal scale there is often an open-ended distribution.

B

What score can be added to the following data set in order for the new median to be 12? 3, 3, 6, 10, 14, 15, 17 a. 10 b. 16 c. 13 d. 12

B

Check My Work If one of the scores in a distribution is changed from X = 15 to X = 12, which of the following must be true? a. The median will decrease. b. The mode will decrease. c. The mean will decrease. d. All of the mean, median, and mode will change in some way.

C

In a symmetrical distribution, which of the following must be true? 50% of the scores are located below the median. 50% of the scores are located below the mean. a. I only b. II only c. I and II d. neither I nor II

C