Question 1

Which of the following is NOT a descriptive statistic?

Accepted Answer

A)   The mean
B)   The standard deviation
C)   The p-value
D)   The standard score C

Question 2

Which of the following statements is true about a random sample?

Accepted Answer

A)   The mean of the sample will be the best guess of the mean of the population, no matter how large the sample is.
B)   The mean of the sample will be the best guess of the mean of the population but only in very large samples.
C)   The mean of the sample will provide the best guess of the mean of the population, but only if the sample is normally distributed.
D)   The mean of the sample will provide the best guess of the mean of the population, but only if there are outliers in the sample. A

Question 3

Which of the following represents the mode of the following eight numbers: 1 2 2 4 5 5 5 8

Accepted Answer

A)   2
B)   3
C)   4
D)   5 D

Question 4

A researcher measures all of the students in her class, and determines that the mean of their IQ scores is 105. This information is a(n)

Accepted Answer

A)   inferential statistic.
B)   descriptive statistic.
C)   analyzing statistic.
D)   control variable.

Question 5

After all of the data have been entered into the computer, the first thing that the researcher should do is to

Accepted Answer

A)   transform the data.
B)   check and clean the data.
C)   conduct the statistical analyses.
D)   delete responses that do not support the theory.

Question 6

Imagine the distribution of salaries in a large corporation. Which of the following statistics is likely to be the largest?

Accepted Answer

A)   The median
B)   The mean
C)   The mode
D)   The minimum

Question 7

Joe has a score of 8 on a variable that has a mean of 10 and a standard deviation of 2. What is Joe's standard score on the variable?

Accepted Answer

A)   12
B)   -1
C)   8
D)   -2

Question 8

Computers are useful for collecting and analyzing statistical data because

Accepted Answer

A)   they are less expensive than analyzing data by hand.
B)   they allow p-values to be calculated.
C)   they can decrease calculation errors.
D)   new methods of statistical analysis are not necessary.

Question 9

Which of the following measures dispersion?

Accepted Answer

A)   Mean
B)   Percentile rank
C)   Sum of squares
D)   Mode

Question 10

Nominal variables, such as gender and ethnicity, are usually entered into a data analysis program as

Accepted Answer

A)   letters corresponding to each level of the variable.
B)   a ratio scale.
C)   numbers corresponding to each level of the variable.
D)   words such as male, female, black, and white.

Question 11

Which of the following is used to specify how precisely the population mean has been estimated?

Accepted Answer

A)   The unbiased estimator
B)   The sample mean
C)   The size of the population
D)   The confidence interval

Question 12

The difference between a person's score on the variable (x) minus the mean of the variable is known as the

Accepted Answer

A)   confidence interval.
B)   mean deviation.
C)   degrees of freedom.
D)   margin of error.

Question 13

Which of the following is NOT a reason for deleting the data of a participant?

Accepted Answer

A)   The participant's responses were not in the predicted direction.
B)   The participant did not pass the suspicion check.
C)   The participant had a large number of unusual responses.
D)   The participant was not able to perform the necessary task.

Question 14

A researcher might delete a participant's responses when

Accepted Answer

A)   the responses from the individual are very extreme or unusual.
B)   no other responses are missing for that participant.
C)   the participant's responses do not correspond with the hypothesis.
D)   the participant gave an above average response to each question.

Question 15

Which of the following measures central tendency?

Accepted Answer

A)   Mode
B)   Standard deviation
C)   Sum of squares
D)   Variance

Question 16

Which of the following statistics is used to indicate how accurately a sample mean predicts a population mean?

Accepted Answer

A)   The sum of squares
B)   The F value
C)   The z score
D)   The confidence interval

Question 17

Which of the following is NOT part of preparing data for statistical analysis?

Accepted Answer

A)   Entering data into the computer
B)   Computing descriptive statistics
C)   Checking for missing data
D)   Checking the distribution of the population parameters

Question 18

If A = 5, B = 4 and C = 2, then Σ (A, B, C) =

Accepted Answer

A)   5
B)   -1
C)   40
D)   11

Question 19

Which of the following is NOT a method of checking and cleaning the data?

Accepted Answer

A)   Comparing the entered data with the original questionnaires
B)   Calculating descriptive statistics
C)   Computing a frequency distribution
D)   Creating new data for participants with missing data

Question 20

Descriptive statistics represent the data from a ________ whereas parameters represent the data from a __________.

Accepted Answer

A)   sample; population
B)   population; sample
C)   normal distribution; control group
D)   binomial distribution; population

Exam 16: Data Preparation and Univariate Statistics