What is the difference between an experiment and observational study? How does this affect conclusions?
What determines whether we can make generalizations about our conclusions?
Explain the concept of randomization in an experiment and how it justifies causal conclusions.
Name and explain a type of sampling bias you have learned about.
Explain what correlation measures.
If a scatterplot has a value of r = .9, does that mean there must be a linear relationship between the variables? Explain.
What does the phrase ‘correlation \(\neq\) causation’ mean in your own words?
What form of relationship needs to exist between quantitative variables to perform linear regression?
Explain what extrapolation is and why we should probably try to avoid it.
What does “adjusted \(R^2\)” account for that “multiple \(R^2\)” does not in a linear model?
What different types of questions do CIs and Hypothesis testing answer?
Describe the difference between the Null hypothesis and the Alternate hypothesis. Which one are we trying to show is true?
Why do we calculate a test-statistic?
What does the test-statistic tell us in the context of a hypothesis test?
Why do we sometimes call tests left, right, or two-tailed tests?
What is the definition of a p-value? (SUPER IMPORTANT)
What does the p-value tell us for a hypothesis test?
How does the sample size affect the test-statistic, and as a consequence the p-value, with everything else held constant?
How does the standard error affect the test-statistic, and as a consequence the p-value, with everything else held constant?
What is the difference between ‘statistical significance’ and ‘practical significance’?
What is a Type I error and what is another name for it?
What is a Type II error and what is another name for it?
What type of error occurs if H0 is False but we fail to reject it?
What type of error occurs if H0 is True but we do reject it?
What does the ‘significance level’ refer to in hypothesis testing?
Explain why using \(\alpha\) = 0.05 as a strict cut-off for significance is problematic
What should determine the value we use for our significance level of a hypothesis test?
Explain in your own words what is meant by the following phrase: “Over time it appears the p-value has become a gatekeeper for whether work is publishable.”
What is power in the context of a scientific experiment?
Explain the concept of hypothesis testing. Avenues of thought: What is this method used for and briefly outline the logic behind it and steps needed to perform a hypothesis test.
Explain the concept of ANOVA. Avenues of thought: What types of questions is this method used for, what problem is it solving, what does it quantify?
Explain in detail something that you learned during this course but did not show up on this exam. (not testing or MLR!)