Question 1

Approximately what percentage of the cases represented by the normal curve fall between ‒3 and +3 standard deviations from the mean?

Accepted Answer

A)   34
B)   68
C)   95
D)   100 D

Question 2

If a set of standardized test scores is normally distributed,having a mean of 75 and a standard deviation of 6,approximately 95 percent of the scores are somewhere between

Accepted Answer

A)   72 and 78.
B)   75 and 87.
C)   69 and 81.
D)   63 and 87. D

Question 3

Stan believes that humans use only 10 percent of their brain.He can't remember where he learned this information but is convinced that it is accurate.What would you suggest Stan do to confirm or disconfirm this information?

Accepted Answer

A)   conduct his own study on this to confirm the information
B)   try to find the source of the information so that he can quote it when sharing the information with others
C)   make sure that he shares this valuable information with others
D)   use critical thinking when presented with such round,undocumented numbers D

Question 4

Jenn earned a 72 on her first psychology exam,a 70 on the second exam,and a 71 on the third exam.What can be said about her exam scores?

Accepted Answer

A)   They are a reliable representation of her performance in the class.
B)   She needs to take more exams in order to determine a reliable idea of her class performance.
C)   They do not represent her class performance.
D)   They demonstrate variations in variability and reliability.

Question 5

To discover the extent to which economic status can be used to predict political preferences,researchers are most likely to use

Accepted Answer

A)   standard deviations.
B)   measures of central tendency.
C)   correlational measures.
D)   the means.

Question 6

The illusion that uncontrollable events are correlated with our actions is facilitated by a phenomenon known as

Accepted Answer

A)   regression toward the mean.
B)   the correlation coefficient.
C)   the normal curve.
D)   the standard deviation.

Question 7

A correlation between physical attractiveness and dating frequency of +0.60 would indicate that

Accepted Answer

A)   physical attractiveness has no causal influence on dating frequency.
B)   more frequent dating is associated with lower levels of physical attractiveness.
C)   it is impossible to predict levels of physical attractiveness based on knowledge of dating frequency.
D)   less frequent dating is associated with lower levels of physical attractiveness.

Question 8

If the points on a scatterplot are clustered in a pattern that extends from the upper left to the lower right,this would suggest that the two variables depicted are

Accepted Answer

A)   operationally defined.
B)   positively correlated.
C)   negatively correlated.
D)   not correlated.

Question 9

To determine whether a difference between groups is reliable and statistically significant,you would use

Accepted Answer

A)   representative samples.
B)   data observations.
C)   increased number of participants.
D)   inferential statistics.

Question 10

A lopsided distribution of scores in which the mean is much larger than both the mode and median is said to be

Accepted Answer

A)   statistically significant.
B)   extrapolated.
C)   a standard deviation.
D)   skewed.

Question 11

A scatterplot graphically depicts the

Accepted Answer

A)   standard deviation of a distribution of scores.
B)   arithmetic average of a distribution of scores.
C)   total population from which samples may be drawn.
D)   degree of relationship between two variables.

Question 12

When you read a bar graph,it is most important for you to

Accepted Answer

A)   mentally transform the data into a normal curve.
B)   identify the value of the standard deviation.
C)   note the range and size of the scale values.
D)   identify the correct measure of central tendency.

Question 13

Approximately 68 percent of the cases represented by the normal curve fall within ________ standard deviation(s)of the mean.

Accepted Answer

A)   1
B)   2
C)   3
D)   34

Question 14

Which of the following correlations expresses the strongest degree of relationship between two variables?

Accepted Answer

A)   +0.10
B)   -0.67
C)   -0.10
D)   +0.59

Question 15

Lee believes that if someone walks under a ladder,they will have bad luck.His belief is based on his experience with people walking under a ladder and then having bad luck.Lee's belief is an example of

Accepted Answer

A)   a negative correlation.
B)   illusory correlation.
C)   regression toward the mean.
D)   a positive correlation.

Question 16

The difference between the highest and lowest scores in a distribution is the

Accepted Answer

A)   mean.
B)   range.
C)   median.
D)   standard deviation.

Question 17

The mean of a distribution of scores is the

Accepted Answer

A)   most frequently occurring score.
B)   arithmetic average of all the scores.
C)   least frequently occurring score.
D)   score exceeded by 50 percent of all the scores.

Question 18

Researchers organize data using

Accepted Answer

A)   inferential statistics.
B)   the correlation coefficient.
C)   descriptive statistics.
D)   measures of variation.

Question 19

In a group of five individuals,two report annual incomes of $10,000,and the other three report incomes of $14,000,$15,000,and $31,000,respectively.The mode of this group's distribution of annual incomes is

Accepted Answer

A)   $10,000.
B)   $15,000.
C)   $16,000.
D)   $31,000.

Question 20

Gene believes he is much more likely to win the state lottery if he chooses the numbers than if the numbers are randomly generated by a computer program.Gene's belief best illustrates

Accepted Answer

A)   regression toward the mean.
B)   a normal curve.
C)   an illusion of control.
D)   a scatterplot.

Exam 16: Statistical Reasoning in Everyday Life