Deck 3: Descriptive Statistics

Question 1

Which of the following is a parameter?

A) S
B) σ
C) T-score
D) M

Answer 1

B

Question 2

Population is to sample as:

A) Roman is to Greek.
B) Parameter is to statistic.
C) Leg is to body.
D) Guessing is to knowing.

Answer 2

B

Question 3

Fifty-five scores were obtained from a sit-up test given to sixth-grade children. The highest score was 52, and the lowest score was 7. What is the range of these scores?

A) 27.5
B) 45
C) 59
D) 364

Answer 3

B

Question 4

If a graph were constructed for the data resulting from a written exam on which a few students scored low but almost all of the students scored very high, which term would best describe the resulting curve?

A) Mesokurtic
B) Skewed
C) Trimodal
D) Platykurtic

Question 5

Which of the following traits is TRUE for the normal curve?

A) Asymmetrical
B) Leptokurtic
C) Mesokurtic
D) Platykurtic

Question 6

If a histogram were constructed for a distribution of scores having a mean of 60 and a median of 80, which term would best describe its shape?

A) Skewed
B) Normal
C) Symmetrical
D) Bimodal

Question 7

Which of the following curves would most likely be normally distributed?

A) The heights of males and females aged 20 to 40.
B) The frequency of heart attacks in males for ages 20 to 80.
C) The grip strength of females aged 20 to 80.
D) The weight of all male students at a university.

Question 8

In a distribution having 56 scores, what score is the median?

A) The 28th score
B) The 28.5th score
C) The 29th score
D) Cannot determine without the raw data

Question 9

Which measure of central tendency is most appropriate for use with a very positively skewed distribution?

A) Mode
B) Median
C) Mean
D) All are equally appropriate

Question 10

If the sum of N scores is 143, the median of the scores is 13, and the scores are normally distributed, what is N?

A) 13
B) 1859
C) 11
D) Cannot determine

Question 11

Using the following data, what is the most representative score in this distribution?
30, 12, 7, 7, 6, 5, 3, 2, 0

A) 5
B) 6
C) 7
D) 8

Question 12

Using the following data, which measure of central tendency would change most if the highest score were 15 instead of 30?
30, 12, 7, 7, 6, 5, 3, 2, 0

A) Range
B) Mean
C) Median
D) Mode

Question 13

Using the following data, what is the standard deviation of this population (to the nearest one-tenth)?
30, 12, 7, 7, 6, 5, 3, 2, 0

A) 11.3
B) 9.0
C) 8.4
D) 8.0

Question 14

Which of the following is NOT a measure of variability?

A) Correlation
B) Standard deviation
C) Range
D) Semi-interquartile range

Question 15

The deviation values for six of seven scores in a distribution are: 5, 2, 0, -2, -3 and -4. What is the deviation value for the seventh score?

A) 2.0
B) 2.6
C) 5.0
D) 16.0

Question 16

If the standard deviation of a population is 10, which of the following is most likely to be the value of the standard deviation of a sample from that population?

A) 9
B) 10
C) 11
D) 12

Question 17

What is the definition of variance?

A) A measure of the variability of scores in a distribution
B) The square of the standard deviation
C) The average squared deviation from the mean
D) All of the above

Question 18

In a normal distribution with a mean of 73.0 and a standard deviation of 6.4, what is the value of the median?

A) 60.2
B) 66.6
C) 73.0
D) 79.4
E) Not possible to determine from information given

Question 19

Suppose you determined that the mean IQ of a population is 100. What name is given to this piece of information?

A) Estimate
B) Prediction
C) Parameter
D) Statistic

Question 20

Which of the following is NOT a measure of the center of a distribution?

A) Percentile
B) Mean
C) Median
D) Mode

Question 21

The sum of the deviation values for eight scores from a distribution of 10 scores is -10. What is the sum of the deviation values for the other two scores?

A) 0
B) 2
C) 10
D) Need raw scores to determine

Question 22

What is the standard deviation of a population if the sum of the squared deviations is 81 and there are 9 people in the population?

A) The square root of 3
B) 1
C) 3
D) 9

Question 23

What is the reason to work with samples rather than populations?

A) Populations are continually changing.
B) Researchers can rarely test a population.
C) Statistical methods are designed to work only with samples.
D) Measurements from populations are biased.

Question 24

Which measurement of variability is usually reported with the mean?

A) Range
B) Variance
C) Standard deviation
D) Semi-interquartile range

Question 25

A distribution has a mean (x̄) of 30, a median of 25, and a mode of 23. Describe the distribution.

A) Positively skewed
B) Platykurtic
C) Leptokurtic
D) Very unusual
E) Negatively skewed

Question 26

$\begin{array}{lcc}& \text { Mean } &\text {Standard } \\& &\text { Deviation } \\ \text { Distribution \#1 }& 80&6 \\ \text { Distribution \#2 }& 60 & 8 \\ \text { Distribution \#3 }& 70& 7 \\\end{array}$


-Using the information above, which distribution is the most heterogeneous?

A) 1
B) 2
C) 3
D) Cannot determine

Question 27

$\begin{array}{lcc}& \text { Mean } &\text {Standard } \\& &\text { Deviation } \\ \text { Distribution \#1 }& 80&6 \\ \text { Distribution \#2 }& 60 & 8 \\ \text { Distribution \#3 }& 70& 7 \\\end{array}$


-Using the information above, which distribution is the most homogeneous?

A) 1
B) 2
C) 3
D) Cannot determine

Question 28

Suppose you are discussing the homogeneity and heterogeneity of your clients' weight-training results with one of your colleagues. Which of the following terms will you probably use in the discussion?

A) Mean
B) Percentile
C) Standard deviation
D) Correlation

Question 29

Describe a data matrix.

A) Rows of people and columns of people
B) Rows of numbers and columns of variables
C) Rows of participants and columns of variables
D) Rows of variables and columns of data
E) Rows of numbers and columns of subjects

Question 30

If every score in a distribution were to be increased by 12 points, what would be the effect on the mean and the median?

A) The mean would not change, but the median would increase by 12 points.
B) Both the mean and the median would increase by 12 points.
C) The mean would increase by 12 points, but the median would not change.
D) None of the above

Question 31

Which of the following is NOT affected by the VALUE of every score in the distribution from which it is calculated?

A) The mean
B) The standard deviation
C) The median
D) The mean deviation

Question 32

What type of measure is B, if B is defined as the difference between score values representing the 90th percentile rank and the 10th percentile rank?

A) Central tendency
B) Correlation
C) Prediction
D) Variability

Question 33

For a set of 5,000 scores, the mean is 98, the median is 100, and the mode is 102. Which of the following is TRUE about this distribution?

A) It is skewed negatively.
B) It is skewed positively.
C) It is symmetric.
D) It is homogeneous.

Question 34

If a set of scores is transformed by adding a constant (other than zero) to each score, which of the following statistics would remain unchanged?

A) Mean
B) Median
C) Mode
D) Standard deviation

Question 35

No meaningful interpretation can be attached to the original or raw scores obtained on a test unless which of the following is/are known?

A) Mean
B) Standard deviation
C) Shape of the distribution
D) All of the above