Research & Design Analysis Exam #3 Review

a researcher has used stratified random samping for their study about different attachment styles in romantic relationships of 5000 couples, with deliberate oversampling of queer couples compared to straight couples. What should they do to ensure that the study sample is representative of the population?

Weigh the final results according to actual proportions in the population

What is problematic for the internal validity of correlational studies?

third-varibale problem and directionality problem

Identify the null hypothesis for the following: Children who are visited by medical clowns recover from pneumonia faster than children who receive standard medical care.

μStandard medical care - μClown medical care = 0

Define frequency claims

claims that are more likely to prioritize external validity, whereas the other two types of claims may more often be comfortable with unknown external validity. 

Asking participants to report on their opinions and beliefs in a survey constitutes a ____ measure.

self-report

Michelin stars are highly coveted in the restaurant industry because many people use the Michelin guide as a way to assess restaurant quality. There are restaurants with different stars to signify the quality: 1 star ("high-quality cooking, worth a stop"), 2 stars ("excellent cooking, worth a detour"), and 3 stars ("Exceptional cuisine, worth a special detour"). These stars are akin to a(n) ____ survey format.

Likert scale

What is NOT a characteristic of an independent variable?

researchers do not have control over this variable

Confidence Interval

the width of precision around an estimate

effect size

the strength of a group difference or relationship

point estimate

an intital single estimate of the true value in a population

When it comes to making inferences about the effect of the independent variable on the dependent variable, ____ uses p-values for a binary decision, whereas ___ uses the magnitude and precision of an effect for a continuous decision.

NHST; confidence interval approach

Which of the following are problematic for statistical validity in a correlational study?

outliers and restriction of range

Which predictor's 95% confidence interval (CI) is most precise?

Predictor	Beta [95% CI]	Significance
Exposure to sex on TV	0.25 [0.14, 0.36]	*
Age	0.33 [0.20, 0.46]

exposure to sex on TV

What is NOT an example of a quasi-experimental variable?

different versions of an exam

Which of the following samples is most likely to generalize to its population of interest?

stratified random sample of 120

What is an illustration of self-selection?

A researcher recruits participants who responded to an online ad of the study

r-coefficient

statistic that is used to quantify the strength of the association between two variables

Which validity is irrelevant to association claims?

Internal validity

What kind of survey approach was used in this example item?

Indicate the degree of happiness, all things considered, of your marriage (1 = extremely unhappy; 7 = perfectly happy).

Likert scale

Effect size tells us…

How strong of a relationship there is between two variables AND How large of a difference there is between two groups of an independent variable

What type of analysis matches this research question: Does the association depend on another variable?

moderation

What type of analysis matches this research question: Is the association accounted for by another variable?

third varibale/control varibale

What type of analysis matches this research question: Does another variable underlie the association?

mediation

what is a p-value?

The probability of observing the result if the null hypothesis was actually true

Having 19,000 participants in a study improves its ____ validity.

statistical

Which of the following 95% CIs are most precise?

(-8,-6)

Siddharth et al.’s (2018) study about frequency of sitting and MTL thickness only had 35 participants, which could limit its…

Statistical validity

A researcher who invites patients at a hospital by listing all their names and then asking every 10th person to participate is using…

systematic sampling

If we fail to detect a true effect of the independent variable, we are making a mistake, such that we fail to reject the null…

When the null is actually false (Type II error, beta)

Dr. French’s study showed that the correlation between work-family culture and job satisfaction was weaker for low-income workers compared to high-income workers (French & Agars, 2016). In this case, income is a… 

Modertaing variable

Which type of validity is most limited in quasi-experiments compared to true experiments?

Internal

Dr. Buchanan recruited participants who decided to volunteer at a local charity and compared them to a group of participants who decided against volunteering. Although both groups were similar at the start of the study, Dr. Buchanan found significant benefits to wellbeing and sense of purpose in the volunteer group compared to the non-volunteer group both 3 and 6 months later. Which of the following problems could limit the claim that volunteering causes improvements to wellbeing and sense of purpose? 

Selection Effects and Demand Characteristics

Michelin stars are highly coveted in the restaurant industry because many people use the Michelin guide as a way to assess restaurant quality. There are restaurants with different stars to signify the quality: 1 star ("high-quality cooking, worth a stop"), 2 stars ("excellent cooking, worth a detour"), and 3 stars ("Exceptional cuisine, worth a special detour"). These stars are akin to a(n) ____ survey format.

semantic differential

What is the problem with the following survey item? Select all that apply.
How much do you agree that our excellent customer service and high-quality products make us the best choice for all your shopping needs?

It’s a double-barreled question and its a leading question

Why is high interrater reliability not enough to mitigate the influence of observer bias?

The raters may be biased in the same direction

To investigate work stress and burnout in American medical doctors, a researcher emails 1,000 randomly selected registered primary care physicians, 200 from each state. This is an example of…

stratified random sampling

To investigate social media factors that influence body image in teenaged girls, a researcher DMs a survey to 400 TikTok users between the ages of 13-17 who follow a body-positive influencer. This is an example of…

purposive sampling

Dr. Loaiza conducts her memory experiments by asking participants to remember briefly presented colored dots in a highly controlled lab setting. Which statement is most likely to be true?

The studies likely have high internal validity but low external validity

What validity is most important for random assignment?

internal validity

What validity is most important for random sampling?

external validity

What validity is most important for sample size?

statistical validity

When conducting a poll about the percentage of CSU students who drink coffee, adding more people to the sample will…

Reduce the estimate’s margin of error

Define direction

whether the value is positive or negative

Define precision

how wide the confidence interval around the value is

Define strength

how close the value is to 1 or -1

Multivariate designs differ from bivariate designs because...

They can consider moderating and mediating variables, They can hold constant one or more other measured variables, and They involve more than two measured variables