Question 1

Because government corruption is difficult to measure directly, a student used citizen perceptions of corruption as reported in a survey as a variable, even though it is not an ideal measure .Perceptions of corruption in this case is an example of

A)A proxy measure
B)An omitted variable
C)A control variable
D)An unmeasured variable

A

Accepted Answer

A proxy measure is used when direct measurement of a variable is difficult, so an alternative indicator that is believed to closely relate to the variable of interest is used instead. In this case, citizen perceptions of corruption serve as a proxy for actual corruption levels.

Question 2

Which is NOT an example of an observational study?&#10;A)Researchers assign participants to teach either older or younger people how to use a computer to test whether participants appear more frustrated teaching older people.&#10;B)A manager uses sales records to compare the performance of different employees.&#10;C)A professor studies the relationship between democracy and per capita income using country-level data from the World Bank.&#10;D)A political scientist uses data from a random sample survey of 2000 US adults to examine the effect of media exposure on people's trust of government.

Accepted Answer

In choice A, researchers are assigning participants to different groups and manipulating the conditions of the experiment, which makes it an experiment rather than an observational study. Observational studies involve observing subjects without intervening or altering the conditions.

Question 3

An agency analyst is studying factors which motivate employees to work, but fails to consider job perks in her equation .In this case, job perks are a ___ variable since they are in the background, and may potentially bias the estimated causal relationship between her independent and dependent variables.

A)Lurking
B)Covert
C)Concealed
D)Clandestine

A

Accepted Answer

Lurking variables are those not included in the study but can influence the outcome, potentially biasing the results. Job perks fit this description as they can affect employee motivation but were not considered by the analyst.

Question 4

A researcher is interested in conditioning the data, where she will break it into groups based upon student GPA's .In this situation, the researcher is going to _____ the datA.&#10;A)Allocate&#10;B)Intensify&#10;C)Partition&#10;D)Stratify

Accepted Answer

Stratifying data involves dividing it into subgroups based on certain criteria, such as GPA, to analyze or manage the subsets separately. This approach is commonly used in research to ensure representation across different strata or levels of the variable of interest.

Question 5

To investigate the impact of population density on crime, a researcher compared average crime rates in low and high density neighborhoods .To control for poverty, which is related to both density and crime, he further stratified the data into low and high poverty neighborhoods .Instead of using this method of stratification, multiple regression analysis is often preferable because

A)It can accommodate more than one or two control variables
B)It is not limited to categorical variables
C)A fuller range of values of both the independent and control variables can be taken into account
D)All of the above

Accepted Answer

Multiple regression analysis is often preferred over stratification because it can handle multiple control variables, is not limited to categorical variables, and can account for a fuller range of values for both independent and control variables, making it a more versatile and comprehensive analytical tool.

Question 6

High school students from low-income families sometimes work after school to bring in extra income .Because of the hours they spend working, they have less time to do homework, which can lead to poorer grades .A researcher explores the effect of family income on grades .What type of variable is working part time in this study?

A)Common cause
B)Intervening variable
C)Control variable
D)None of the above

Accepted Answer

Working part-time acts as an intervening variable in this study because it is a variable that mediates the relationship between family income and grades, explaining how or why a certain effect occurs.

Question 7

Program evaluators seek to estimate the causal effect of a program (X) on an outcome (Y) using observational datA .The evaluators attempt to adjust their estimate for common causes (Z) that influence both X and Y .In this evaluation, the common causes (Z) are best described as

A)Intervening variables
B)Independent variables
C)Control variables
D)All of the above

Accepted Answer

Control variables are factors that the researchers want to hold constant or account for to isolate the effect of the independent variable (X) on the dependent variable (Y). In this context, common causes (Z) that influence both X and Y are adjusted for in the analysis to accurately estimate the causal effect, making them control variables.

Question 8

To collect data as part of an observational study, a researcher may use:&#10;A)Telephone surveys&#10;B)Administrative record data&#10;C)Secondary data from large government surveys&#10;D)All of the above

Accepted Answer

All the options listed are methods through which data can be collected in an observational study. Telephone surveys, administrative record data, and secondary data from large government surveys do not require manipulation of variables or intervention by the researcher, fitting the criteria for observational study methods.

Question 9

A study found higher rates of crime in cities with an international airport, compared to cities without an international airport .But the study failed to take account of the size of the city (population), and bigger cities tend both to have more crime and to have international airports .The findings of this study suffer from

A)Measurement bias
B)Omitted variable bias
C)Sample selection bias
D)All of the above

Accepted Answer

The study's findings suffer from omitted variable bias because it failed to account for the size of the city, which is a relevant variable that affects both the likelihood of a city having an international airport and the rate of crime.

Question 10

A(n) __ is a variable that causally occurs before both X and Y, and is viewed as a potential common cause.&#10;A)Cofounder&#10;B)Replacement&#10;C)Distortion&#10;D)Antecedent

Accepted Answer

An antecedent is a variable that causally occurs before both X and Y, and is viewed as a potential common cause.

Question 11

A study found that eating junk food is related to getting cancer .Which of these statements is true?&#10;A)Adding control variables could increase the relationship between junk food and cancer.&#10;B)Adding control variables could decrease the relationship between junk food and cancer.&#10;C)Adding control variables could eliminate the relationship between junk food and cancer.&#10;D)All of the above

Accepted Answer

The answer of A study found that eating junk food...

Deck 12: Observational Studies With Control Variables