Question 1

Students who study little for tests tend to make more errors on tests; students who study a lot tend to make fewer errors.If a researcher collected data on both amount of studying and test scores, he or she would likely spot an)

Accepted Answer

A negative correlation indicates that as one variable increases, the other decreases. In this case, as the amount of studying increases, the number of errors on tests decreases.

Question 2

When you pair two variables, and as one increases so does the other, your data will show

Accepted Answer

A positive correlation indicates a relationship where as one variable increases, the other variable also increases.

Question 3

If a researcher believes that participants in a single group will score differently from one another on a task, the researcher can find out if that is true by looking at the

Accepted Answer

The standard deviation measures the variability or spread of scores within a group, so if the researcher suspects that participants in a single group will score differently from one another, the standard deviation can indicate whether this is true. The mean and median both measure central tendency and would not necessarily indicate differences in scores between participants. The correlation coefficient measures the relationship between two variables and would not be appropriate in this situation of analyzing scores within a single group.

Question 4

The most frequently occurring score in a data set is known as the

Accepted Answer

The mode is the most frequently occurring score in a data set. The mean is the average of all the scores in the data set, the range is the difference between the highest and lowest scores, and the standard deviation is a measure of the spread or variability of the scores. However, none of these options refer to the most frequently occurring score, except for the mode.

Question 5

The mean, median, and mode are all examples of

Accepted Answer

The mean, median, and mode are all measures of central tendency, or ways to summarize the center of a set of data.

Question 6

Which of the following best represents a medium negative correlation?

Accepted Answer

A medium negative correlation is represented by a negative value closer to -1 than to 0. The correct notation for a negative correlation in the choices provided is not clearly represented due to formatting issues, but choice B seems to imply a negative value (indicated by the presence of a minus sign), and the value closest to -0.5 or -0.6 would typically represent a medium negative correlation. The other options are positive values or are not clearly negative correlations.

Question 7

If you created a scatterplot of your data, what type of statistic would you have computed?

Accepted Answer

If you created a scatterplot of your data, you would have computed a correlation coefficient, as a scatterplot is used to visualize the relationship between two variables and the correlation coefficient measures the strength and direction of that relationship.

Question 8

If you want to know how far apart scores in a data set tend to be, you could use the

Accepted Answer

The standard deviation measures the amount of variation or dispersion in a set of data. It shows how much the scores in a data set vary from the mean. Therefore, it is the best choice for determining how far apart scores in a data set tend to be.

Question 9

When a researcher cannot manipulate variables in a project, he or she is forced to collect naturally occurring data.The data analysis would probably involve

Accepted Answer

Correlational analysis is used to examine the relationship between variables when manipulation is not possible, allowing researchers to observe naturally occurring relationships.

Question 10

When you pair two variables, and as one increases the other decreases, your data will show

Accepted Answer

A negative correlation is when as one variable increases, the other decreases. This is shown through a negative correlation coefficient, which indicates the strength and direction of the relationship between two variables. The other options do not accurately describe this type of relationship.

Question 11

Carlos reads an article looking for a measure of central tendency.Which of the following might he find?

Accepted Answer

The measure of central tendency refers to the value that represents the center of a distribution of data. The most common measures of central tendency are the mean, median and mode. Out of the options given, only the median is a measure of central tendency. The standard deviation is a measure of variability, inferential statistics involve making predictions about a population based on a sample, and the correlation coefficient measures the strength and direction of a linear relationship between two variables.

Question 12

The values in a data set span from 60 to 90.If a researcher knows this, then the researcher is aware of the

Accepted Answer

The range of a data set refers to the difference between the largest and smallest values. In this case, the range would be 90-60=30. Knowing the range provides information about the spread of values in the data set. The other options (standard deviation, median, and mode) are measures of central tendency or dispersion that require additional information to calculate.

Question 13

A store owner wants to make sure she has enough shirts in the right sizes in her inventory, so she buys a lot of shirts in the most popular size.In order to make this purchase, what type of statistic would she want to know?

Accepted Answer

The store owner would want to know the mode, which is the most commonly occurring size, in order to ensure she has enough shirts in the right sizes in her inventory.

Question 14

Researchers have found that taller people tend to have higher levels of self-esteem than shorter people.This pattern of data reflects

Accepted Answer

The pattern of data reflects a positive correlation, as taller height is positively associated with higher levels of self-esteem.

Question 15

If you list a set of scores from the lowest value to the highest, then take the middle value to indicate what a typical score is, you are using the

Accepted Answer

The median is the middle value of a set of scores when listed in order. It is a measure of central tendency that is not affected by extreme scores or outliers, unlike the mean. The mode refers to the most frequently occurring score, while the range is a measure of variability and represents the difference between the highest and lowest scores.

Question 16

The range and standard deviation are examples of

Accepted Answer

The range and standard deviation are both measures of variability, specifically how spread out a set of data is. They do not represent central tendency (such as mean, median, or mode) or correlation between variables, and they are not inferential statistics (which involve making inferences about populations based on samples).

Question 17

The statistic that involves the basic arithmetic average of a set of scores is known as the

Accepted Answer

The arithmetic average is calculated by adding up all the scores in a set and then dividing by the number of scores. This is the definition of the mean. The mode is the most common score in a set, the range is the difference between the highest and lowest scores, and the median is the middle score when the set is ordered from lowest to highest. However, the question specifically asks for the statistic that involves the basic arithmetic average, which is the mean.

Question 18

Why is the range often the least useful measure of central tendency?

Accepted Answer

The range only identifies the most extreme scores and does not take into account the distribution of scores between the highest and lowest. It does not provide information about the typical or central values of the data.

Question 19

Research has shown that some types of behavioral or psychiatric disorders are more prevalent among people with low levels of education.This pattern of data is best represented by

Accepted Answer

The pattern of data indicating that certain disorders are more prevalent among people with low education levels represents a negative correlation, as higher education levels are correlated with a lower likelihood of these disorders. The other options (validity, descriptive statistics, and standard deviations) do not accurately reflect this pattern of data.

Question 20

Which of the following is closest to a perfect positive correlation?

Accepted Answer

A perfect positive correlation would be indicated by a correlation coefficient of 1.0. Of the given choices, 0.98 is the closest to 1.0.

Quiz 2: Research Methodology