Question 1

Characteristics of populations are known as:
A)Concepts
B)Parameters
C)Statistics
D)Estimations

Accepted Answer

Characteristics of populations are known as parameters.

Question 2

Here is a set of scores: 5,3,7,3,6,2,5,3.The median of this set of scores is:
A)2
B)3
C)4
D)4.5

Accepted Answer

D

Question 3

In a normal distribution,approximately what percentage of scores falls between one standard deviation below the mean and one standard deviation above the mean?
A)16%
B)50%
C)68%
D)90%

Accepted Answer

The Empirical Rule (also known as the 68-95-99.7 Rule) states that in a normal distribution, approximately 68% of scores fall within one standard deviation above or below the mean. Therefore, approximately 34% of scores fall between one standard deviation below the mean and the mean, and another 34% fall between the mean and one standard deviation above the mean. Adding these two percentages together gives us 68%.

Question 4

Here is a set of scores: 5,3,7,3,6,2,5,3.The mean of this set of scores is:
A)3
B)4
C)4.25
D)4.5

Accepted Answer

To find the mean, add up all the numbers and divide by the total number of numbers in the set:
(5+3+7+3+6+2+5+3) / 8 = 4.25

Question 5

The measure(s)of central tendency that is/are appropriate for use with nominal data is/are:
A)the median only.
B)the mode only.
C)the median and the mean.
D)the median and the mode.

Accepted Answer

The measure of central tendency appropriate for nominal data is the mode, as it identifies the most frequently occurring category. The median and mean cannot be calculated for nominal data since there is no inherent ordering or hierarchy among categories.

Question 6

When reporting growth data,the most useful measure of central tendency is the:
A)arithmetic mean
B)mode
C)median
D)geometric mean

Accepted Answer

The geometric mean is the most useful measure of central tendency when reporting growth data because it accurately calculates the average rate of return of a set of values that are multiplied together, making it ideal for understanding growth rates over time.

Question 7

When the median is the measure of central tendency,the _____ is the most appropriate and informative measure of dispersion.
A)standard deviation
B)interquartile range
C)range
D)mean

Accepted Answer

When the median is chosen as the measure of central tendency, the interquartile range (IQR) is the most appropriate measure of dispersion. This is because the IQR is calculated based on the range between the 25th and 75th percentile of the data. Therefore, it provides a measure of how spread out the middle 50% of the data is, which is the segment that the median represents. The range (choice C) is sensitive to outliers and might not be a good measure of dispersion in all cases. The standard deviation (choice A) is based on the mean and might not be appropriate when the median is the measure of central tendency. The mean (choice D) might also not be appropriate when the median is the measure of central tendency, especially when the data is skewed.

Question 8

Frank Fitness found a correlation coefficient of -.74 between hours of strenuous exercise each week and a standard measure of body mass.He interprets this to mean that there is a:
A)strong,positive correlation between hours of strenuous exercise and body mass.
B)strong,negative correlation between hours of strenuous exercise and body mass.
C)weak,positive correlation between hours of strenuous exercise and body mass.
D)weak,negative correlation between hours of strenuous exercise and body mass.

Accepted Answer

A correlation coefficient of -.74 indicates a strong negative correlation, meaning that as the number of hours of strenuous exercise increases, body mass decreases.

Question 9

Marialexa conducts an economic study and asks her participants to provide information about their family incomes.First,they are asked to check one box from a list of three,indicating whether they consider themselves low-income,middle-income,or high-income.She refers to this as the self-identification variable.Then,they are asked (if they are willing)to provide their annual income in dollars.She refers to this as the dollar-figure variable.The study is both confidential and anonymous,and most people answer both questions.Which of the following statements accurately describes Marialexa's dependent variables?
A)Both are continuous
B)The self-identification variable is discrete and the dollar-figure variable is continuous
C)Both are discrete
D)The self-identification variable is continuous and the dollar-figure variable is discrete

Accepted Answer

The self-identification variable has a distinct and limited number of options (low, middle, or high income), making it a discrete variable. The dollar-figure variable, on the other hand, can take on any numerical value within a certain range, making it a continuous variable. Therefore, option B correctly identifies that the self-identification variable is discrete and the dollar-figure variable is continuous.

Question 10

Marialexa conducts an economic study and asks her participants to provide information about their family incomes.First,they are asked to check one box from a list of three,indicating whether they consider themselves low-income,middle-income,or high-income.She refers to this as the self-identification variable.Then,they are asked (if they are willing)to provide their annual income in dollars.She refers to this as the dollar-figure variable.The study is both confidential and anonymous,and most people answer both questions.Which of the following statements accurately describes the data Marialexa collects?
A)The self-identification data are ordinal data and the dollar-figure data are ratio data.
B)The self-identification data are nominal data and the dollar-figure data are ratio data.
C)The self-identification data and the dollar-figure data both are interval data.
D)The self-identification data and the dollar-figure data both are ratio data.

Accepted Answer

The self-identification data are ordinal because they have a clear, ordered ranking (low, middle, high income) without specifying the exact differences between these categories. The dollar-figure data are ratio data because they have a true zero point (an income of $0) and the differences between values are meaningful.

Question 11

Characteristics of samples are known as:
A)Concepts
B)Parameters
C)Statistics
D)Estimations

Accepted Answer

Characteristics of samples are called statistics, while characteristics of populations are called parameters. Estimations refer to the process of estimating a parameter based on a sample or samples, while concepts refer to general ideas or theories.

Question 12

When summarizing ordinal data,the most useful measure of central tendency is the:
A)arithmetic mean
B)mode
C)median
D)geometric mean

Accepted Answer

When summarizing ordinal data, the most useful measure of central tendency is the median because it is less affected by extreme values and skewed distributions compared to the arithmetic mean. The mode may not be appropriate for ordinal data as multiple values may have the same frequency. The geometric mean is used for data that has a multiplicative relationship, which is not applicable to ordinal data.

Question 13

The z-score,or standard score,allows the research to determine:
A)how far a target individual's score is from the group mean.
B)what percentage of individuals in the sample scored above the target individual.
C)the mean for the population based on the mean for the sample.
D)what percentage of individuals in the sample scored below the target individual.

Accepted Answer

The z-score measures how many standard deviations a given score is from the mean of the group, indicating how far a target individual's score is from the group mean.

Question 14

A distribution of scores that is positively skewed will have a small number of scores that
A)are very high.
B)are very low.
C)are clustered around the midpoint.
D)are all the same.

Accepted Answer

A positively skewed distribution means that there are a small number of extremely high scores which pull the skewness away from the mean. Therefore, option A - "are very high" - is the best choice.

Question 15

An exam was given to two sections of the same course.In Section 1,the exam mean was 51 and the standard deviation was 7.In Section 2,the exam mean was 51 and the standard deviation was 13.Which of the following conclusions is accurate?
A)Section 1 did better on the exam than Section 2.
B)Section 1 scores were more variable than Section 2.
C)Section 1 scores were less variable than Section 2.
D)Section 1 did less well on the exam than Section 2.

Accepted Answer

The standard deviation measures the variability of the data. Since the standard deviation of Section 1 (7) is less than the standard deviation of Section 2 (13), this means that the scores in Section 1 were less variable. However, we cannot make any conclusions about which section did better on the exam based solely on the means and standard deviations.

Question 16

The percentile rank allows the researcher to determine:
A)how far a target individual's score is from the group mean.
B)what percentage of individuals in the sample scored above the target individual.
C)the mean for the population based on the mean for the sample.
D)what percentage of individuals in the sample scored below the target individual.

Accepted Answer

The percentile rank indicates the percentage of scores in its frequency distribution that are equal to or lower than it, thus showing what percentage of individuals in the sample scored below the target individual.

Question 17

Here is a set of scores: 5,3,7,3,6,2,5,3.The mode of this set of scores is:
A)3
B)4
C)4.22
D)4.5

Accepted Answer

The mode is the number that appears most frequently in a set of scores. In this set, the number 3 appears three times, which is more than any other number. Therefore, the mode is 3.

Question 18

Three of the following factors are associated with a relatively small standard error of the mean.Which one is NOT?
A)Sample size is relatively large.
B)Sample standard deviation is relatively small.
C)The variance in the sample is relatively large.
D)The sample is highly representative of the population.

Accepted Answer

The standard error of the mean decreases with a larger sample size, a smaller sample standard deviation, and when the sample is highly representative of the population. A relatively large variance in the sample would actually increase the standard error of the mean, not decrease it.

Question 19

How are inferential statistics different from descriptive statistics?
A)Descriptive statistics allow one to draw inferences from the sample to a target population.
B)Descriptive statistics verify the accuracy of the inferential statistics.
C)Inferential statistics describe the results of a study.
D)Inferential statistics allow one to draw inferences from the sample to a target population.

Accepted Answer

Inferential statistics allow one to generalize findings from a sample to a larger population, whereas descriptive statistics simply summarize or describe the data collected from the sample.

Question 20

Danzell is a purchasing agent for a major grocery store chain.He has noticed over the years that the higher the outdoor temperature,the more likely people are to buy fresh fruit.Based on Danzell's observations,we would say the correlation between outdoor temperature and buying of fresh fruit is:
A)positive.
B)negative.
C)causal.
D)moderate.

Accepted Answer

Danzell's observations show that as one variable (outdoor temperature) increases, so does the other variable (buying of fresh fruit). This indicates a positive correlation between the two.

Quiz 8: Analyzing Quantitative Data

Characteristics of populations are known as:

Here is a set of scores: 5,3,7,3,6,2,5,3.The median of this set of scores is:

In a normal distribution,approximately what percentage of scores falls between one standard deviation below the mean and one standard deviation above the mean?

Here is a set of scores: 5,3,7,3,6,2,5,3.The mean of this set of scores is:

The measure(s) of central tendency that is/are appropriate for use with nominal data is/are:

When reporting growth data,the most useful measure of central tendency is the:

When the median is the measure of central tendency,the _____ is the most appropriate and informative measure of dispersion.

Frank Fitness found a correlation coefficient of -.74 between hours of strenuous exercise each week and a standard measure of body mass.He interprets this to mean that there is a:

Characteristics of samples are known as:

When summarizing ordinal data,the most useful measure of central tendency is the:

The z-score,or standard score,allows the research to determine:

A distribution of scores that is positively skewed will have a small number of scores that

An exam was given to two sections of the same course.In Section 1,the exam mean was 51 and the standard deviation was 7.In Section 2,the exam mean was 51 and the standard deviation was 13.Which of the following conclusions is accurate?

The percentile rank allows the researcher to determine:

Here is a set of scores: 5,3,7,3,6,2,5,3.The mode of this set of scores is:

Three of the following factors are associated with a relatively small standard error of the mean.Which one is NOT?

How are inferential statistics different from descriptive statistics?

Danzell is a purchasing agent for a major grocery store chain.He has noticed over the years that the higher the outdoor temperature,the more likely people are to buy fresh fruit.Based on Danzell's observations,we would say the correlation between outdoor temperature and buying of fresh fruit is: