Research Methods

Identify each variable below as either categorical or quantitative: -number of pets a person owns -type of pet a person owns

-number of pets a person owns: quantitative -type of pet a person owns: categorical

Below are several of the claims that set the stage for the article. Identify each as one of the three types of claims we learned about. 1. "a Pew survey found that 95 percent of teenagers had access to a smartphone": 2. "One widely publicized 2017 study in the journal Clinical Psychological Science found that the longer adolescents were engaged with screens, the greater their likelihood of having symptoms of depression or of attempting suicide.": 3. "...the more time they spent on nonscreen activities, like playing sports or hanging out with friends, the less likely they were to experience those problems": OPTIONS: association causal frequency

1. "a Pew survey found that 95 percent of teenagers had access to a smartphone": frequency 2. "One widely publicized 2017 study in the journal Clinical Psychological Science found that the longer adolescents were engaged with screens, the greater their likelihood of having symptoms of depression or of attempting suicide.": association 3. "...the more time they spent on nonscreen activities, like playing sports or hanging out with friends, the less likely they were to experience those problems": association

Which of the following is true of the relationship between hypotheses and theories? A) Hypotheses are used to determine if a theory is accurate. B) Multiple theories are needed to test whether a hypothesis is accurate. C) Hypotheses and theories are synonymous terms. D) Theories are used to determine if a hypothesis is accurate.

A) Hypotheses are used to determine if a theory is accurate. Ch. 1

Which aspects of construct validity could we assess with a scatterplot? A) criterion, convergent, discriminant B) face and content C) content and criterion D) scatterplots should only be used to assess reliability

A) criterion, convergent, discriminant

Given a regression equation of Y' = .005(X) + .40 for predicting college GPA from SAT critical reading scores, the beta coefficient of .005 indicates that the correlation between college GPAs and SAT I scores is ____. A) positive B) strong C) statistically significant D) negative

A) positive

In the tenth paragraph, one researcher advocates for understanding more about "for who" and "under what circumstances" screen time is tied to poor well-being, which is summarized by the science writer as, "A screen-related activity may be beneficial or harmful depending on who is doing it, how much they're doing it, when they're doing it and what they're not doing instead." In other words, we need to understand more about key ______ in the relationship between screen time and well-being, which will improve the _______ validity of claims made from this research.

Answer 1: moderators Answer 2: external

For the linear regression equation, Y = bX + a, which of the following X, Y points will definitely be on the regression line? A) a,b B) 0,a C) b,a D) 0,b

B) 0,a

Which threats to construct validity in observational research involve a change in behavior by the participants? A) unclear operational definitions and observer effects B) observer effects and reactivity C) observer bias and reactivity D) observer bias and observer effects

B) Observer effects and reactivity

A friend tells you that they found a correlation of -1.65 between hours of sleep per night and GPA. Why should you be immediately skeptical of their finding? A) Pearson correlations range from 0 to 1 B) Pearson correlations range from -1 to 1 C) correlations are invalid for association claims D) more sleep should be related to higher GPAs

B) Pearson correlations range from -1 to 1

If a measurement appears to a non-expert to be a plausible operationalization of a conceptual variable, then it has: A) reliability B) face validity C) statistical validity D) criterion validity

B) face validity Ch.5

To calculate a z-score for a given raw score: A) subtract the mean, then divide by the variance B) subtract the mean, then divide by the standard deviation C) divide by the standard deviation, then subtract the mean D) divide by the standard deviation, then add the mean

B) subtract the mean, then divide by the standard deviation

How do reverse-worded items address shortcuts? A) they are easier for people to read B) they slow down readers, making them answer more carefully C) they give people more answer options D) they ask each question twice so the participant answers twice

B) they slow down readers, making them answer more carefully

Which of the following could not be a value of r^2 for regression: A) 1.0 B) .05 C) 1.3 D) 0

C) 1.3 (range is 0 to 1)

Which one of the following numbers for the standard error of estimate would indicate the best regression fit? A) 50 B) 1000 C) 100 D) 10

D) 10 (smaller is better)

Given a regression equation of Y' = .005(X) + .40 for predicting college GPA from SAT critical reading scores, the predicted GPA for a student with an SAT score of 650 would be: A) 3.00 B) .40 C) 3.25 D) 3.65

D) 3.65

Below is a grouped frequency table for self-reported age of students in a large undergraduate class at the University of Las Vegas, Nevada. Based on the table, what percentage of students with age data are in their 20s? (columns are frequency, percent, valid percent, and cumulative percent) A) 93.8% (cumulative percent until 20-29) B) 36.6% (percent at 20-29) C) 183% (frequency at 20-29) D) 36.7% (valid percent at 20-29)

D) 36.7% (valid percent at 20-29)

When you need to organize and summarize a set of variables to characterize their central tendency, variability, and nature of their relationships, you should use _____________ statistics. When you need to test a prediction about population parameters based on your sample data, you should use _____________ statistics. A) inferential; inferential B) descriptive; descriptive C) inferential; descriptive D) descriptive; inferential

D) descriptive; inferential

Dr. Gahn decides to create a questionnaire asking about people's attitudes toward immigration (a socially sensitive topic). He should be most concerned about which of the following? A) faking bad B) negatively worded answers C) people self-reporting more than they can know D) fence sitting

D) fence sitting

Which type of validity is the most difficult to maximize in correlational research designs? A) construct B) external C) statistical D) internal

D) internal

What does it mean if a finding is "statistically significant"? A) the null hypothesis was retained B) the effect is big C) the statistical test was done correctly D) the null hypothesis was rejected

D) the null hypothesis was rejected

There are multiple operational definitions that are possible for any one conceptual definition True or False

True Ch. 3

The standard deviation can never be: A) smaller than the mean B) negative C) zero D) larger than the mean

B) negative

Below is a distribution for self-reported age of students in a large undergraduate class at the University of Las Vegas, Nevada. What shape best describes the distribution? (higher frequency at low end of data for age, tail/lower frequency with increased age) A) negatively skewed B) normal symmetric C) positively skewed D) bi-modal

C) positively skewed

Identify level of measurement for each variable. Levels of measurement can be used more than once: - number of sports played in high school - rankings assigned to the top 10 sports books of all time - type of sport played in high school: individual, team, none

- number of sports played in high school: ratio - rankings assigned to the top 10 sports books of all time: ordinal - type of sport played in high school: individual, team, none: nominal

How do the interquartile range (IQR) and the standard deviation (SD) differ? A) SD is influenced by the variability of all the values for a variable, whereas IQR is only influenced by values closest to the median (middle 50% of the data) B) IQR is more influenced by extreme values than the SD C) IQR is influenced by the variability of all the values for a variable, whereas SD is only influenced by values closest to the median (middle 50% of the data) D) IQR is a measure of central tendency, whereas SD measures variability

A) SD is influenced by the variability of all the values for a variable, whereas IQR is only influenced by values closest to the median (middle 50% of the data)

The fifth paragraph also evaluates an aspect of validity in the studies conducted about links between screen time and well-being: "Gathering data on so many behaviors also means that respondents aren't always asked about topics in detail. This is particularly problematic when studying tech use. In past decades, if researchers asked how much time a person spent with a device — TV, say — they knew basically what happened during that window. But "screen time" today can range from texting friends to using social media to passively watching videos to memorizing notes for class — all very different experiences with potentially very different effects." What validity is the writer critiquing here? A) construct B) internal C) statistical D) external

A) construct

You read about a study reporting an association between sleep quality and anxiety. The study found an association between these two variables by surveying college students to measure their self-reported sleep quality and their self-reported anxiety. You are intrigued and decide to manipulate sleep quality by having college students come to a lab to sleep there for two weeks. One group sleeps in a room optimized for good sleep (no screens allowed, cool temperatures) and another sleeps in a hot room with distracting screens. This design improves the ability to control variables affecting sleep like ambient noise and light and temperature. However, only 2% of the college students invited decide to participate because they don't want to sleep in a lab. The change in study design reflects a decrease of _______ validity, and an increase in _______ validity. A) external; internal B) internal; external C) statistical; external D) internal; statistical

A) external; internal Ch. 3

For observational research it is advisable to always have at least two research assistants conduct ratings in order to establish the _______________ of their observational measures before publishing their results. A) inter-rater reliability B) observer effects C) internal reliability D) test-retest reliability

A) inter-rater reliability

Below is a distribution for self-reported age of students in a large undergraduate class at the University of Las Vegas, Nevada. The mean is 20.77 years old. Based on the distribution shape, would you expect the median to be a lower or higher age? (higher frequency at low end of data for age, tail/lower frequency with increased age) A) lower B) the same C) higher

A) lower

Why are curvilinear relationships hard to detect with Pearson correlation coefficients (r)? A) pearson r assumes the relationship could be modeled with a straight line B) curvilinear relationships require a large amount of scores C) curvilinear relationships involve categorical variables D) the sum of squares for X and Y cannot be computed if they have a curvilinear relationship

A) pearson r assumes the relationship could be modeled with a straight line

Which of the following is a true of the distinction between scientific journals and popular magazines? A) scientific journal articles are peer-reviewed; popular magazine articles are not B) scientific journals are published quarterly; popular magazines are published monthly C) scientific journals are published quarterly; popular magazines are published monthly D) scientific journal article findings have limited jargon and references to empirical studies; popular magazines have a lot of jargon and are targeted to an audience of scientists in that area of research

A) scientific journal articles are peer-reviewed; popular magazine articles are not Ch. 2

A psychiatrist is testing a drug that he predicts will decrease depressive symptoms. He has given the drug to all his patients, and all of them have experienced a decrease in depressive symptoms. Although this is interesting, his conclusions from this experience are weak because he does not have: A) a falsifiable prediction B) a comparison group that did not receive the drug C) a way to measure depressive symptoms D) a hypothesis

B) a comparison group that did not receive the drug Ch. 2

Why do we use n-1 as the denominator when calculating the variance of a sample? A) we only use n-1 to get sample standard deviation B) because when computing variance one score in the data is not free to vary in the sample C) because with samples we always overestimate the population variance D) because when computing variance n-1 scores in the data are not free to vary in the sample

B) because when computing variance one score in the data is not free to vary in the sample

College entrance exams like the SAT are meant to measure the construct "aptitude for college-level work." Which of the following would be a good measure for testing the SAT test's criterion validity? A) number of hours studying for the SAT B) college grades C) score on another entrance exam like the ACT D) test of creativity

B) college grades

Einstein famously said, "No amount of experimentation can ever prove me right; a single experiment can prove me wrong". What principle of good theories is he referring to? A) affirmation B) falsifiability C) parsimony D) empiricism

B) falsifiability Ch. 1

After a study reported that taking notes by hand improved memory retention for video materials in a laboratory experiment, a researcher decided to see whether the effect would generalize to psychology course lectures. In his new study, he surveyed students in introductory psychology classes about how they take notes, and examined the relationship between their note-taking method and final exam score. The change in study design reflects a decrease of _______ validity, and an increase in _______ validity. A) statistical; internal B) internal; external C) external; statistical D) external; internal

B) internal; external Ch.3

Suppose we collect data from our class to learn more about everyone's favorite flavor of ice-cream. To do this, we conduct a survey, and each student selects their favorite ice-cream flavor from a list of the ten most common flavors in stores. What central tendency statistic is most appropriate for summarizing this data? A) cumulative percent B) mean C) mode D) median

B) mean

In lecture we watched a video of the "Marshmallow test" -- which has been used as a measure of self-control. This is an example of what type of measurement? A) other-report B) observational C) physiological D) self-report

B) observational Ch 5

Null and alternative hypotheses are statements about: A) effect sizes B) population parameters C) sample parameters D) sample statistics

B) population parameters

Dr. E finds an association between sleep duration and problem solving. Students that report sleeping longer on a typical week-night also showed better performance on a test assessing analytical problem solving. This is an example of which type of association? A) causal association B) positive association C) negative association D) no association

B) positive association Ch. 3

Below is a grouped frequency table for self-reported age of students in a large undergraduate class at the University of Las Vegas, Nevada. Based on the table, what percentage of students are under 30? (columns are frequency, percent, valid percent, and cumulative percent) A) 36.7% (valid percent for 20-29) B) 98.2% (cumulative percent until 30-39) C) 93.8% (cumulative percent until 20-29) D) 6.2% (not anywhere in table)

C) 93.8% (cumulative percent until 20-29)

______ is the approach of basing decisions on data, and using insights from data to develop, support, and/or challenge a theory. A) rationalism B) translation C) empiricism D) parsimony

C) Empiricism Ch. 1

For which measure would inter-rater reliability be applicable? A) an emotional intelligence test comprised of 10 multiple-choice questions B) a self-report measure of life satisfaction C) a behavioral measure of happiness operationalized as the number of times a person smiles during the study D) a physiological measure of happiness operationalized by stress hormones in saliva

C) a behavioral measure of happiness operationalized as the number of times a person smiles during the study

Which of the following is the difference between claims based on personal experience (anecdotal claims) and frequency claims? A) anecdotal claims involve a single variable; frequency claims involve two variables B) anecdotal claims appear in newspapers; frequency claims appear in journals C) anecdotal claims are not based on empirical research but frequency claims are D) anecdotal claims are less interesting than frequency claims

C) anecdotal claims are not based on empirical research but frequency claims are Ch. 3

Harry studies childhood amnesia and is aware of several competing theories proposing how the phenomenon works. He designs his study to collect data that he predicts will specifically support his theory, but does not collect data that could refute his theory and support alternatives. What bias is affecting his scientific thinking? A) confounds in experience B) availability heuristic C) confirmation bias D) the good story

C) confirmation bias Ch. 2

Which of the following is a helpful tool for visualizing test-retest reliability and inter-rater reliability: A) cronbach's alpha B) bar graph C) scatterplot D) correlation coefficient

C) scatterplot Ch. 5

For a distribution of raw scores with a mean of 50, the Z-score for a raw score of 60 is calculated to be -2.00. Why must this Z-score be incorrect? A) the Z-score should be smaller since the raw score is only 10 units different than the mean B) Z-scores range from -1 to 1 C) the Z-score should be positive since the raw score is above the mean D) Z-scores range from 0 to 1

C) the Z-score should be positive since the raw score is above the mean

Martin has found a correlation of r = .13 between the two variables of using prescription stimulants (e.g., Adderall) and frontal lobe activity. This correlation is more likely to be statistically significant if: A) prescription stimulant was measured as a categorical variable (yes/no) B) prescription stimulant use was measured really precisely C) the sample size is really large D) the study can be applied to the real world

C) the sample size is really large

Given the following scores for 3 variables, how does the sample variance compare for the 3 variables? sub.: 1, 2, 3 variable A: 4, 5, 6 variable B: 49, 50, 51 variable C: 499, 500, 501 A) variable C has the highest variance B) variable A has the highest variance C) they are the same D) variance cannot be computed with 3 subjects

C) they are the same

When taking a scientific approach to learn about a topic, results from research studies are a superior source than personal experience because: A) research is empirical B) research studies utilize confounds for clearer conclusions C) researchers are free of bias in their intuitions D) research studies allow for better comparison groups that you can get from personal experience

D) research studies allow for better comparison groups than you get from personal experience Ch. 2

Which measure of variability below utilizes all values in the data? A) range B) mean C) inter-quartile range D) standard deviation

D) standard deviation

In the ninth paragraph, results are summarized from one of the study teams, saying "...they found that "digital-technology use has a small negative association with adolescent well-being." But to put that association in context, they used the same method to test the relationship between adolescent well-being and other variables. And in all the data sets, smoking marijuana and being bullied were more closely linked with decreased well-being than tech use was; at the same time, getting enough sleep and regularly eating breakfast were more closely tied to positive feelings than screen time was to negative ones. In fact, the strength of the association screen time had with well-being was similar to neutral factors like wearing glasses or regularly eating potatoes." What type of validity is being evaluated in this discussion of the relative strength of the effect? A) internal B) construct C) external D) statistical

D) statistical

Why are larger samples NOT always more representative? A) results from non-random sampling often generalize to public even with small samples B) larger samples may include too much variability in the data C) the margin of error increases as the same size increases D) the size of the sample is not as important as how the sample was selected

D) the size of the sample is not as important as how the sample was selected

For which of the scenarios below would the Pearson correlation definitely be zero? A) when there is range restriction B) when both variables have high variability C) when there is a bivariate outlier D) when one variable is actually a constant

D) when one variable is actually a constant

In the fourth paragraph the writer evaluates the validity of results from correlational designs examining the relationship between screen time and well-being, stating that "Even if their responses are entirely accurate, that data can't speak to cause and effect. If the most depressed teenagers also use the most digital technology, for example, there's no way to say if the technology use caused their low mood or vice versa, or if other factors were involved." The difficulty of correlational designs to provide strong evidence about cause-and-effect refers to their weakness in construct validity. OPTIONS: construct, internal, external, statistical Specifically, if the data can't be used to tell whether screen-time leads to depressive symptoms, or whether kids with depressive symptoms are more likely to use screens, the ______ cannot be resolved. OPTIONS: temporal precedence, third variable problem, covariance Additionally, if "other factors" may be involved that cannot be evaluated with the data collected (e.g., physical activity levels, sleep hygiene), the ______ cannot be resolved. OPTIONS: temporal precedence, third variable problem, covariance

The difficulty of correlational designs to provide strong evidence about cause-and-effect refers to their weakness in construct validity. ANS: internal Specifically, if the data can't be used to tell whether screen-time leads to depressive symptoms, or whether kids with depressive symptoms are more likely to use screens, the ______ cannot be resolved. ANS: temporal precedence Additionally, if "other factors" may be involved that cannot be evaluated with the data collected (e.g., physical activity levels, sleep hygiene), the ______ cannot be resolved. ANS: third variable problem