Question 1

Which of the following is NOT a possible correlation coefficient?

Accepted Answer

A correlation coefficient can range from -1.00 to +1.00. Therefore, +1.72 is not a possible correlation coefficient.

Question 2

Ethan wants to measure the relationship between two variables, weight and height. To calculate the correlation coefficient for his data set, Ethan should first:

Accepted Answer

To calculate the correlation coefficient, both variables should be converted into z scores to standardize the data and allow for meaningful comparison. The other options are not relevant for calculating the correlation coefficient.

Question 3

A _____ correlation coefficient indicates that as one variable increases, the other tends to increase, and a _____ correlation coefficient indicates that as one variable increases, the other tends to decrease.

Accepted Answer

A positive correlation coefficient indicates that as one variable increases, the other tends to increase, while a negative correlation coefficient indicates that as one variable increases, the other tends to decrease. Therefore, choice D is correct.

Question 4

A _____ correlation coefficient indicates that as one variable increases, the other tends to decrease.

Accepted Answer

A negative correlation coefficient indicates an inverse relationship between two variables. As one variable increases, the other tends to decrease.

Question 5

When Brooke plotted her data in a graph that showed the relationship between variable A and variable B, she found that they clustered in a pattern that extended from the upper left-hand corner of the graph to the lower right-hand corner.Brooke has plotted a _____ that shows a _____.

Accepted Answer

A scatter diagram with data points extending from the upper left to the lower right indicates a negative correlation, where as one variable increases, the other decreases.

Question 6

Which of the following correlation coefficients would indicate the strongest relationship between high school grade-point average and first year college grade-point average?

Accepted Answer

B) A correlation coefficient of +0.72 indicates a strong positive relationship between high school grade-point average and first year college grade-point average.

Question 7

A scatter diagram graphically depicts:

Accepted Answer

A scatter diagram is a type of graph used to display the relationship between two variables. It consists of a series of dots, each representing a single data point, plotted along two axes. The position of each dot indicates the value of the two variables for that particular data point, allowing the researcher to visualize the relationship between the two variables. Therefore, the correct answer is D - the scatter diagram graphically depicts the relationship between two variables.

Question 8

Assume that annual income is related to level of education.Which of the following correlation coefficients would indicate the strongest relationship between the two variables?

Accepted Answer

The correlation coefficient measures the strength and direction of the relationship between two variables. A value of +1 indicates a perfect positive relationship, while a value of -1 indicates a perfect negative relationship. A value of 0 indicates no relationship between the two variables. Therefore, a correlation coefficient of +0.65 indicates a strong positive relationship between annual income and level of education, which suggests that people with higher levels of education tend to earn higher incomes. A correlation coefficient of -0.35 indicates a moderate negative relationship, which suggests that people with lower levels of education tend to earn lower incomes. A correlation coefficient of -0.01 or +0.10 indicates a weak or very weak relationship and may not be considered statistically significant.

Question 9

Suppose that it has been shown that the lower the family income, the higher the incidence of psychological problems.This finding would demonstrate that there is a _____ between family income and psychological problems.

Accepted Answer

The lower the family income, the higher the incidence of psychological problems suggests that as one variable (family income) decreases, the other variable (psychological problems) increases. This indicates a negative correlation. However, this finding does not necessarily establish a cause-and-effect relationship, as there could be other variables that impact both family income and psychological problems.

Question 10

The closer a correlation coefficient is to _____, the stronger the relationship between the two variables.

Accepted Answer

A correlation coefficient ranges from -1.00 to +1.00, with -1.00 indicating a perfect negative correlation, +1.00 indicating a perfect positive correlation, and 0 indicating no correlation. Therefore, the closer the correlation coefficient is to -1.00 or +1.00, the stronger the relationship between the two variables.

Question 11

Of the following correlation coefficients, which represents the strongest relationship between two factors?

Accepted Answer

The absolute value of -0.80 is larger than the absolute values of +0.03, +0.36, and -0.15, indicating a stronger correlation between the two factors.

Question 12

Ethan analyzed the data from his correlational research project and found a correlation coefficient of -0.15. Ethan canconclude that the two variables:

Accepted Answer

A correlation coefficient of -0.15 indicates a weak negative correlation between the two variables.

Question 13

A _____ is a graph that represents the relationship between two variables.

Accepted Answer

A scatter diagram or scatter plot is a graph that represents the relationship between two variables. The other options (frequency polygon, histogram, and standard normal curve) are also types of graphs, but they do not specifically depict the relationship between two variables.

Question 14

Bailey discovered that there was a negative correlation between the amount of time spent watching TV and level of education. If the correlation coefficient is relatively high,Bailey can conclude that:

Accepted Answer

A negative correlation means as one variable increases, the other decreases. In this case, as the amount of time spent watching TV increases, the level of education decreases. A relatively high correlation coefficient indicates a strong relationship between the two variables, but it does not imply causation. Therefore, option A is not the best choice. Option D is contradicted by the negative correlation. Therefore, option B is the best choice as it accurately represents the negative correlation.

Question 15

In her research, Dr. Bristow found that the more time students spent studying, the higher their score on the final exam. Dr.Bristow has demonstrated a _____ correlation.

Accepted Answer

A positive correlation means that as one variable increases, the other variable also increases. In this case, as the amount of time spent studying increases, the score on the final exam also increases, which is a positive correlation.

Question 16

Assume that one particular study showed that there is a relatively high negative correlation between exercise and fitness. This would indicate:

Accepted Answer

A negative correlation means that as one variable increases, the other decreases. Therefore, if there is a high negative correlation between exercise and fitness, it would indicate that the less people exercise, the greater their physical fitness. This is counterintuitive, but it may be explained by other factors impacting fitness like genetics or diet.

Question 17

A _____ correlation coefficient indicates that as one variable increases, the other tends to increase.

Accepted Answer

A positive correlation coefficient indicates a positive relationship between two variables, meaning as one variable increases, the other tends to increase as well.

Question 18

A correlation coefficient of -0.88 is to _____ as a correlation coefficient of +0.15 is to _____.

Accepted Answer

A correlation coefficient of -0.88 represents a strong negative correlation, while a correlation coefficient of +0.15 represents a weak positive correlation. Therefore, the best choice is C, which includes a high negative correlation and a low positive correlation.

Question 19

After conducting a statistical analysis of responses to a survey,Professor Balbos finds a correlation of +3.14 between frequency of air travel and frequency of colds. This indicates that:

Accepted Answer

The correlation coefficient ranges from -1 to +1. A value of +3.14 is not possible, indicating a calculation error.

Question 20

Dr. Meeney calculated correlation coefficients for two different sets of data. He found that data set X had a correlation coefficient of -0.75, and data set Y had a correlation coefficient of +0.58. Dr. Meeney can conclude that:

Accepted Answer

The strength of a correlation is determined by the absolute value of the correlation coefficient. Since |-0.75| = 0.75 is greater than |+0.58| = 0.58, set X has a stronger correlation than set Y.

Quiz 13: Psychological Disorders