Taylor Swift
Taylor Swift is planning on going on tour, and she needs your help! She wants to know if the danceability rating of her songs (low or high danceability) influences the happiness score of her fans, which they report in a form sent out at the end of the concert on a scale of 1 to 100. What type of variable is the dependent variable? What type is the independent variable?
Dependent Variable: What is a metric variable?
Independent Variable: What is a categorical variable?
Dr. Lin wants to give a pop quiz to her PSY1900 students (oh no!) to test if completing your PSETs (yes or no) influences how well students do on the quiz (the score students receive, from 0 to 100). What is the independent variable, and what type is it? What is the dependent variable, and what type is it?
Independent Variable: What is completing your PSETs (yes or no)?
IV Type: What is categorial?
Dependent Variable: What is quiz score?
DV Type: What is continuous?
When reporting the output of a statistical test, what are the components you must include?
What are the degrees of freedom, test statistic, and p-value?
Taylor Swift is planning on going on tour, and she needs your help! She wants to know if the danceability rating of the songs she performs (low or high danceability) influences the happiness score of her fans, which they report in a form sent out at the end of the concert on a scale of 1 to 100. What type of test do you recommend that Taylor's team runs?
What is an independent samples t-test?
Dr. Lin wants to give a pop quiz to her PSY1900 students (oh no!) to test if completing your PSETs (yes or no) influences how well students do on the quiz (the score students receive, from 0 to 100). What type of test should she run to determine this?
What is an independent samples t-test?
For a multiple regression test, should you report the R-squared or Adjusted R-squared? Why?
What is Adjusted R-squared because this provides a more stringent cutoff for the amount of variation that can be explained by another variable?
Taylor Swift is going on tour, and she needs your help deciding where in America she should prioritize going to because she is a busy woman and cannot go everywhere. The location options are the Northeast, South, Midwest, or West. Her team sends out a form to a random sample from each region of the country, and participants report how much they like Taylor on a scale of 1 to 100. What type of test should her team run to decide where she should go on tour based on her popularity rating? What test statistic should they report to her?
Test: What is a linear regression?
Statistic: What is a correlation coefficient (r)?
Dr. Lin wants to give a pop quiz to her PSY1900 students (oh no!) to test if completing your PSETs influences how well students do on the quiz (the score students receive, from 0 to 100). After checking the class Canvas, the teaching team realizes that some students sometimes do their PSETs, and sometimes do not. To account for this, they decide to add another category to the independent variable: yes, no, or sometimes completing PSETs. What test should they run now?
What is an F-test (one-way ANOVA or multiple regression)?
When reporting the intercept of a multiple regression test, what should the value of the continuous predictor be? Why?
What is 0 because the intercept tells us the starting value of a variable without the other predictor?
Taylor Swift is going on tour, and she needs your help determining if fans like her songs from her original 1989 album, or 1989 (Taylor's Version). She knows that her song, Blank Space, is her most-streamed single and also in the 1989 album, so she plans to perform that on tour. She wants to know which version — the original or Taylor's Version — of Blank Space fans prefer. Her team sends out a random survey to her fans before releasing 1989 (Taylor's Version), and fans rate how much they like the original Blank Space on a scale of 1 to 100. Then, after 1989 (Taylor's Version) was released one week later, her team sent another survey asking the same fans to rate how much they liked the original Blank Space on a scale of 1 to 100. To determine if the likeness rating changed, which test should her team perform?
What is a paired t-test?
Dr. Lin wants to give a pop quiz to her PSY1900 students (oh no!) to test if completing your PSETs influences how well students do on the quiz (the score students receive, from 0 to 100). After checking the class Canvas, the teaching team realizes that some students sometimes do their PSETs, and sometimes do not. To account for this, they decide to add another category to the independent variable: yes, no, or sometimes completing PSETs. If they wanted to do this analysis in R, how should they set up the dummy variable(s)?
What is make 3 dummy variables, each of which is dichotomous (0 or 1)?
Find the mistake in the following analysis:
After running the independent-samples t-test, the output is t = 9.32, p < 0.05.
Bonus point if you can identify two!
What are degrees of freedom?
Bonus: What is context/relationship you are considering?
Taylor Swift is going on tour, and she needs your help deciding which songs she should play. She knows that her song, Blank Space, is her most-streamed single, so she plans to perform that on tour. She wants to know if her other song, Cruel Summer, should also be performed on tour. Her team sends out a random survey to fans across the country, and they rate how much they like both songs. To decide whether or not to play Cruel Summer on tour, what test should her team run?
What is correlation to find correlation coefficient r?
Dr. Lin wants to give a pop quiz to her PSY1900 students (oh no!) to test if completing your PSETs influences how well students do on the quiz (the score students receive, from 0 to 100). After checking the class Canvas, the teaching team realizes that some students sometimes do their PSETs, and sometimes do not. To account for this, they decide to add another category to the independent variable: yes, no, or sometimes completing PSETs. They set up the dummy variable as previously described, but a psych student (who heard about this plan) wonders why the teaching team doesn't just make one dummy variable with the reference group as 0. What should they tell this student?
What is having one dummy variable does not account for all 3 categories because dummy variables represent a binary (0 or 1) of the existence or lack thereof of some category, so having 3 categories necessitates 3 dummy variables?
Find the mistake in the following analysis:
Compared to the control group, the group that studied scored 23 points more on the math exam.
Bonus point if you can identify two!
What is "on average scored 23 points more on the math exam"?
Bonus: What is specify the control group?