Question 1

A researcher is planning a study that has one dependent variable and two independent variables. Which data analysis procedure would she use?
A) Simple regression analysis
B) Standard deviation analysis
C) Multiple regression analysis
D) z score analysis

Accepted Answer

Multiple regression analysis is used when there is one dependent variable and two or more independent variables.

Question 2

A researcher gathered the following set of data: 54, 56, 56, 56, 57, 57, 58, 58, 59, 59. Which term would best describe these data?
A) Homogeneous
B) Heterogeneous
C) Skewed
D) Homoscedastic

Accepted Answer

The data set is homogeneous because the values are very similar and close to each other, indicating uniformity.

Question 3

When the points in a scatter plot clearly move in a bottom-left to top-right direction, one has a _______ relationship.
A) Positive
B) Negative
C) Causative
D) None of the above

Accepted Answer

A bottom-left to top-right direction in a scatter plot indicates a positive relationship, where as one variable increases, the other variable also tends to increase.

Question 4

If you sum your scores for a variable and divide that sum by the number of scores in the variable, what do you obtain?
A) Mode
B) Median
C) Mean
D) Variance

Accepted Answer

Mean is the sum of all values divided by the number of values in a dataset.

Question 5

If you square the standard deviation, what do you obtain?
A) Range
B) Variance
C) Percentile rank
D) Median

Accepted Answer

The square of the standard deviation is the variance.

Question 6

If the owner of Microsoft moved into your neighborhood, which of the following statistical indexes for the income in your neighborhood would become radically larger?
A) Mean
B) Median
C) Mode
D) Percentile rank

Accepted Answer

The mean is the average of all the incomes in the neighborhood. If the owner of Microsoft moved in, the mean income would increase significantly because the owner of Microsoft has a very high income.

Question 7

An IQ score of 100 is equivalent to a z score of ____.
A) 15
B) 1
C) 0
D) -1

Accepted Answer

An IQ score of 100 is the average score, which corresponds to a z score of 0, indicating it is at the mean of the distribution.

Question 8

Helen has used vertical bars to represent her categorical data. She has created a:
A) Frequency distribution
B) Histogram
C) Scatterplot
D) Bar graph

Accepted Answer

A bar graph uses vertical bars to represent categorical data, with each bar representing a category and its height representing the frequency or value of that category.

Question 9

A measure of variability is a numerical index:
A) of the central tendency of the data values in a set of data
B) that indicates how spread out the data values are in a set of data
C) that indicates the level of skewness of the data
D) that indicates if two variables vary together

Accepted Answer

A measure of variability is a numerical index that indicates how spread out the data values are in a set of data.

Question 10

In simple regression, the _____ is defined as the predicted change in Y given a one-unit change in X.
A) Y intercept
B) Regression coefficient
C) Error term
D) X intercept

Accepted Answer

The regression coefficient is defined as the predicted change in Y given a one-unit change in X.

Question 11

If you want to determine the relationship between two or more categorical variables, what should you do?
A) Calculate the Pearson Product Moment Correlation Coefficient
B) Construct a contingency table
C) Conduct a regression analysis
D) Conduct an analysis of variance

Accepted Answer

A contingency table is used to analyze the relationship between two or more categorical variables by displaying the frequency distribution of the variables.

Question 12

In a scatter plot, when the dots are close together and fall in a relatively straight slanted line, what does this suggest?
A) A strong positive or negative relationship
B) A curvilinear relationship
C) A dispersal of data that should be discarded
D) A weak positive or negative relationship

Accepted Answer

When the dots in a scatter plot are close together and form a straight slanted line, it indicates a strong linear relationship, either positive or negative, between the variables.

Question 13

While studying families living in an inner city neighborhood (where most of the residents have incomes well below the poverty level), Dr. Westbrook found that one resident was actually a very wealthy individual. In terms of income level this person would be considered:
A) A variance
B) A standard deviation
C) An outlier
D) A mode

Accepted Answer

An outlier is a data point that is significantly different from the other data points in a dataset. In this case, the wealthy individual is an outlier in terms of income level compared to the rest of the residents.

Question 14

If one wishes to visualize the relationship between two quantitative variables, which of the following should be used?
A) A contingency table
B) A bar graph
C) A scatter plot
D) A frequency distribution

Accepted Answer

A scatter plot is a graphical representation of the relationship between two quantitative variables. It shows the values of one variable on the x-axis and the values of the other variable on the y-axis. The points on the scatter plot represent the individual data points.

Question 15

Line graphs should used to depict:
A) Nominal variables only
B) Categorical variables only
C) Trends over time
D) Percentile ranks

Accepted Answer

Line graphs are used to depict trends over time.

Question 16

If you wanted to characterize, summarize, and/or explain data you had collected you would use:
A) Descriptive statistics
B) Inferential statistics
C) Multiple regression
D) Hypothesis testing

Accepted Answer

Descriptive statistics are used to summarize and describe the main features of a dataset, providing simple summaries about the sample and the measures.

Question 17

When the points in a scatter plot clearly move in a top-left to bottom-right direction, one has a _______ relationship.
A) Positive
B) Negative
C) Causative
D) None of the above

Accepted Answer

A top-left to bottom-right direction in a scatter plot indicates a negative relationship, where as one variable increases, the other decreases.

Question 18

Sally wants to graphically represent her data from her study. She collected data on the number of hours her students spent on homework every day of the week. What pictorial representation should she use for her study?
A) A bar graph.
B) A histogram
C) A contingency table
D) A scatter plot

Accepted Answer

The answer of Sally wants to graphically represent her data...

Question 19

Joe wants to make assumptions about characteristics of a population based upon his sample. In order to do this he must use:
A) Descriptive statistics
B) Inferential statistics
C) Multiple regression
D) Point estimates

Accepted Answer

Inferential statistics allow researchers to make inferences about a population based on a sample.

Question 20

Below is a regression equation predicting children's math achievement from their parents' education level (years of education). Y = 1 + 2x, where x is the number of years of parental education.
What would be the predicted score for a child whose parents had 10 years of education?
A) 21
B) 20
C) 12
D) 11

Accepted Answer

The regression equation is Y = 1 + 2x. Plugging in x = 10 (years of parental education), we get Y = 1 + 2(10) = 1 + 20 = 21.

Quiz 18: Descriptive Statistics

A researcher is planning a study that has one dependent variable and two independent variables. Which data analysis procedure would she use?

A researcher gathered the following set of data: 54, 56, 56, 56, 57, 57, 58, 58, 59, 59. Which term would best describe these data?

When the points in a scatter plot clearly move in a bottom-left to top-right direction, one has a _______ relationship.

If you sum your scores for a variable and divide that sum by the number of scores in the variable, what do you obtain?

If you square the standard deviation, what do you obtain?

If the owner of Microsoft moved into your neighborhood, which of the following statistical indexes for the income in your neighborhood would become radically larger?

An IQ score of 100 is equivalent to a z score of ____.

Helen has used vertical bars to represent her categorical data. She has created a:

A measure of variability is a numerical index:

In simple regression, the _____ is defined as the predicted change in Y given a one-unit change in X.

If you want to determine the relationship between two or more categorical variables, what should you do?

In a scatter plot, when the dots are close together and fall in a relatively straight slanted line, what does this suggest?

While studying families living in an inner city neighborhood (where most of the residents have incomes well below the poverty level) , Dr. Westbrook found that one resident was actually a very wealthy individual. In terms of income level this person would be considered:

If one wishes to visualize the relationship between two quantitative variables, which of the following should be used?

Line graphs should used to depict:

If you wanted to characterize, summarize, and/or explain data you had collected you would use:

When the points in a scatter plot clearly move in a top-left to bottom-right direction, one has a _______ relationship.

Sally wants to graphically represent her data from her study. She collected data on the number of hours her students spent on homework every day of the week. What pictorial representation should she use for her study?

Joe wants to make assumptions about characteristics of a population based upon his sample. In order to do this he must use:

Below is a regression equation predicting children's math achievement from their parents' education level (years of education) . Y = 1 + 2x, where x is the number of years of parental education. What would be the predicted score for a child whose parents had 10 years of education?