- Conduct a one-sample t-test for a dataset where μ = 74.2, X = 75.1, sx = 10.2, and n = 81.a. What are the groups for this one-sample t-test?b. What is the null hypothesis for this one-sample
- Using the unstandardized regression equation of ŷi = bxi = aa. Find the values for b and a if r = –0.45, X̅ = 6.9, sx = 0.8, Y = 10.6, and sy = 1.4.b. Find the predicted dependent variable
- Using the unstandardized regression equation of ŷi = bxi + aa. Find the values for b and a if r = +0.35, X̅ = 4.2, sx = 1.5, Y = 3.0, and sy = 2.1.b. Find the predicted dependent variable scores
- Draw a scatterplot for the following correlations:a. r = –0.82b. r = –0.61c. r = –0.22d. r = 0.00e. r = +0.45f. r = +0.66g. r = +0.79h. r = +1.00
- Which correlation coefficient is the strongest?(a) –0.21,(b) –0.62,(c) +0.04,(d) +0.33,(e) +0.49.
- Which correlation value is the strongest and which is the weakest:(a) +0.42,(c) +0.59, (b) –0.87,(d) –0.34.
- Conduct an unpaired two-sample t-test for the following data: X̅1 = 14.8, s1 = 1.99, n1 = 52, X̅1 = 13.2, s2 = 2.89, n2 = 233. For this problem, you should use an α value of .01.a. Explain why an
- Steven is an anthropology student who collected data on the behavior of children of immigrants and children of non-immigrants in a playground setting. He found that children of immigrants spent an
- Jessi conducts a study to determine whether early voting in an election affects how informed the person is when they vote. She theorizes that people who vote early are more motivated to vote and will
- Gagné and Gagnier (2004) studied the classroom behavior of children who were a year younger than their classmates and those who were a typical age for their grade. The children’s teachers rated
- Elias conducts a 3 x 3 ANOVA. His independent variables are socioeconomic status and education level, and his dependent variable is the willingness of a subject to donate to charity. He finds that
- Emily is a sociology student who uses a Wilcoxon rank-sum test to compare the levels of interest in political activity among college students and non-college students. She finds that college students
- Aaron has two interval-level independent variables and an interval-level dependent variable. His R2 value is 0.110.a. Aaron adds another independent variable, and this increases the R2 to 0.155. What
- Interpret the following R2 values:a. 0.744b. 0.312c. 0.004.
- Ahmed has four variables in his data. Three are independent variables: a nominal-level variable and two ratio-level variables. He also has an interval-level dependent variable. What is the
- A nominal variable records the major of students in a sample of (1) sociology students, (2) social work students, and (3) anthropology students.a. How many new variables would have to be created in a
- Pablo’s data consist of a nominal independent variable with four groups and a dependent interval-level variable. What is the appropriate statistical procedure for Pablo’s data?
- Christine has a single, independent, nominal-level variable with two categories and three dependent variables.a. What is the appropriate multivariate statistical procedure for this situation?b. If
- When there are two independent variables and a single dependent variable, why is it better to conduct a 2 x 2 ANOVA instead of two separate one-way ANOVAs?
- Explain when it would be beneficial to calculate Spearman’s ρ instead of Pearson’s r.
- The following questions are about multicollinearity.a. What is multicollinearity?b. Why is multicollinearity a problem in multiple regression?c. What can a data analyst do to reduce the chance of
- Why can it be difficult to detect Simpson’s paradox?
- How can you practice meta-analytic thinking as you read research in your field?
- What is the difference between exploratory factor analysis and confirmatory factor analysis?
- Kyla and Joan are classmates analyzing the same set of data. There are two nominal independent variables and one interval-level dependent variable. Kyla chooses to conduct a two-way ANOVA, while Joan
- Describe the relationship between correlation (or Pearson’s r) and multiple regression.
- What does it mean if a study is said to be a 4 x 2 ANOVA?
- A university collected data on the number of scholarship students that donated to the same scholarship fund when they were alumni. There were three groups of alumni: those receiving athletic
- Customers of four companies were surveyed and placed into three categories: repeat customers, non-repeat satisfied customers, and non repeat/dissatisfied customers.a. What is the null hypothesis for
- In a university political science department, there are 90 students enrolled, 36 males and 54 females. Of the 36 males, 28 eventually graduated, while 8 did not. Of the 54 females, 42 graduated,
- Logan’s favorite sports team has an 80% chance of winning their next game. Convert this value into an odds ratio where his team is the non baseline group and the outcome of interest is a victory.
- In a study of second language learning, Researcher A found that individuals whose parents were bilingual were 2.5 times more likely to be fluent in a second language by age 21 than children whose
- Barnsley, Thompson, and Barnsley (1985, p. 24) examined the birth months of National Hockey League players in the United States and Canada. They hypothesized that traditional rules stating that a
- In a study of the effectiveness of a new vaccine, a researcher found that the relative risk of developing a disease is 0.31 for individuals who have had the vaccine. In the same study, it was
- Explain the third variable problem.
- Samantha found that the correlation between income and self-reported happiness is r = +0.39. She concludes that if more people were wealthy they would be happier. What is the problem with her logic?
- What are the two interpretations of r2?
- What is Type I error inflation, and why is it a problem when conducting multiple NHSTs?
- Answer the following questions about a scenario where the p-value is small (e.g., < .05 or < .01).a. Why would it be incorrect to say that these results are important?b. Why would it also be
- Jim found that the p-value in his study was less than .01. He says, “This means that my null hypothesis is false. My findings are strong enough to replicate.”a. Why are both of Jim’s statements
- Interpret the following AUC values:a. 0.922b. 0.713c. 0.500d. 0.412e. 0.331f. 0.012
- Maddie is a sociology student who found that individuals with high levels of social support were more likely to graduate from college than individuals with low levels, as indicated by the odds ratio
- Kathryn’s sample consists of patients at a psychiatric clinic. In the clinic population, 40% of patients have depression, 28% have anxiety disorders, 15% have eating disorders, 10% have
- Dante gave a survey to the anthropology students in his department. He had 42 female respondents and 31 male respondents. In his department the entire population of students is 59% female and 41%
- Name the four benefits of meta-analysis.
- Define relative risk.
- What is the “file drawer problem,” and why is it a problem in the social sciences?
- What is the relationship between a two-variable chi-squared test and Pearson’s r?
- Explain the relationship between a one-variable chi-squared test and a one-sample t-test.
- Which odds ratio indicates that the baseline group and the non-baseline group are equally likely to experience the outcome of interest?(a) 0.45,(b)1.00,(c)1.33, or (d) 2.05.
- If d = 1.0, what is the equivalent point-biserial correlation value?
- For the unstandardized equation, a is the y-intercept of the regression line. Given the equation for a (which is a = Y̅ - bX̅), explain why the y-intercept of the regression line is always 0 when
- For the unstandardized equation, b is the slope of the regression line. Given the equation for b (which is b = r sy/sx), explain why r is the slope of the regression line when the independent and
- Camilla collected data on the quality of day care (x) and the child’s grades in kindergarten (y). Her data are below:a. Find the correlation between these two variables.b. Write the standardized
- Jane is interested in health psychology, so for a project she collects data on the number of hours that college students watch television per day (x) and the number of hours that they exercise per
- What assumption does the scatterplot below violate? 8 7 3- 1 4 3. 2. 4. 2.
- Using the standardized regression equation of ẑy = rzx, find the predicted dependent variable z-scores if r = +0.10:a. zx = –3.5b. zx = –2.8c. zx = –2.5d. zx = –0.8e. zx = 0.0f. zx = +0.4g.
- Using the standardized regression equation of ẑy = rzx, find the predicted dependent variable z-scores of individuals with the following individuals if r = –0.72:a. zx = –4.0b. zx = –2.9c. zx
- Describe why some outliers distort the regression line and others do not.
- How do you determine whether an outlier is distorting the relationship between two variables?
- What does a scatterplot look like when the homogeneity of residuals assumption is violated?
- Many professions (e.g., medicine, law, architecture) require job applicants to pass a licensing test of basic skills and knowledge in order to work in that field. Examinees who do not pass the test
- What assumption does the scatterplot below violate? 12 10 8 - 2 0 + 2 8 10 12 X variable Y variable
- Explain why regression is not able to make predictions of outliers or of rare events.
- Dallin is a sports fan. As he tracks the performance of different teams, he notices that teams that were poor performers 10 years ago tend to be better teams now, whereas teams that were excellent 10
- Every time she makes a regression equation, Jocelyn converts all her data to z-scores and then uses the standardized regression equation to create the line of best fit. She notices that her
- Peggy collects data for the restaurant where she works. In a sample of regular customers, she collected data on the number of restaurant visits per week (x) and customer satisfaction (y). Both
- Eliza, a family science student, asks married couples to count the number of arguments they have in a month (x) and rate their children’s happiness on a scale from 1 to 7 (y), higher numbers
- Angelica collected data on people’s anxiety levels (x) and life satisfaction (y). The scores are below:a. Calculate the correlation for Angelica’s data.b. What is the null hypothesis for these
- Leigh is an anthropology student who has measured the diameter of clay pots found at an archeological site (x) and the volume of those pots (y). Below are the scores for both variables for the 12
- Tomás is a sociology student who collected data on two variables: perceived level of racism in society (x) and willingness to sign a political petition (y). Below are the scores from the first 8
- Find the correlation value between the two variables below. ID Y 1 6. 5 2 3 1 4 2 4 4 6. 2.
- Explain whether the following relationships are positive correlations or negative correlations.a. People with larger families tend to have better support systems in a crisis.b. Individuals who brush
- Explain the relationship between Pearson’s r and the unpaired-samples t test in terms of the GLM.
- Mason is a sociology student who is interested in how city size influences how people interact with their neighbors. He has three groups in his dataset: (1) inner city dwellers, (2) suburban
- Zachary is a psychology student who is interested in the degree of control that people feel they have in their lives. He has five groups in his dataset: (a) police officers, (b) victims of violent
- Davita is an anthropology student who measures the level of trust in her subjects. In her data higher numbers indicate greater trust of strangers and lower numbers indicate less trust. She divided
- Oi-mon is a sociology student interested in how groups of people choose to travel long distances. He asked four groups of travelers how much they enjoyed long journeys. The four groups were plane
- Nicole is a psychology student interested in the social dynamics of solving problems. She divided her sample into three groups: people who solved problems alone (Group A), people forced to solve
- Liliana collected data about the happiness level of teenagers, young adults, and elderly individuals, with a score of 1 being “very unhappy” and a score of 5 being “very happy.”a. Why is an
- Dave’s university has students from six different Canadian provinces. He surveys a representative sample of students to learn how many hours per week they study. Jim wants toknow if there are any
- Dana wants to compare the grade-point averages (GPAs) for freshman, sophomore, junior, and senior sociology students. If she chooses not to use an ANOVA,a. how many unpaired two-sample t-tests will
- How do you find a critical value in an ANOVA?
- In an ANOVA we can use the information table to make predictions. How do we measurea. individual prediction accuracy?b. overall prediction accuracy?
- Explain why labeling effect sizes as “small,” “medium,” or “large” without any further interpretation is problematic.
- What is the benefit of calculating group means in the information table?
- Explain the connection between the unpaired two-sample t-test and ANOVA.
- In an ANOVA the null hypothesis is that all of the group means are equal to one another. If the null hypothesis is rejected, how do we determine which group mean(s) differ from other mean(s)?
- The effect size for ANOVA is η2. What are the two interpretations of this effect size?
- Some of the formulas in this chapter use the abbreviation k. What does k signify?
- What is the purpose of a Bonferroni correction?
- Conduct a one-sample t-test for a dataset where μ = 14.1, X = 13.7, sx = 0.8, n = 20.a. What are the groups for this one-sample t-test?b. What is the null hypothesis for this one-sample t-test?c.
- Grover, Biswas, and Avasthi (2007) studied people who had long-term delusions, and the authors were interested in whether individuals with another mental disorder had an earlier age of onset than
- Calculate the degrees of freedom for the following sample sizes:a. Group 1: 10; Group 2: 15b. Group 1: 10; Group 2: 1,500c. experimental group: 35; control group: 35d. males: 18; females: 12e.
- What are the guidelines for ensuring that the data in an unpaired two sample t-test meet the assumptions of homogeneity of variance and similar sample sizes?
- What is the correct interpretation of the p-value?
- How do we determine the range of a p-value for a paired-samples t-test?
- What are the four things that determine statistical power?
- Define statistical power and explain why it is important in social science research.
- Explain the relationship between the pooled standard deviation and the pooled variance.