• Fri 5/19 7pm-10pm in Warner 506
• Not a final, but 3rd midterm. Timed at ~1h15m to 1h30m
• Bring your cheatsheets
• Bring a calculator or your smart phone with calculator app

• More conceptual in nature
• Code:
  • Reading/understanding: Fair game
  • Writing: No direct code to write, but pseudocode
• Normal curve of distribution of difficulty

• Lectures 01 through 38 inclusive and cummulative
  • Slides from each lecture
  • Learning Checks
  • Problem set solutions!

• Tidy data. What are the components?
• What is the Grammar of Graphics? How do they tie in with ggplot2?
• What are the first four of the 5NG? What are their distinguishing features?

• All five of the 5NG
• Data manipulation/wrangling
  • 5MV + join
  • Putting it all together: Lec18 - Fri 3/24: The tao of data analysis.
• Sampling, probability, confounding variables, and designed experiments.

• Hypothesis testing
  • Lady tasting tea.
  • There is only one test; it has 5 components.
• Confidence intervals
  • Theory: Sampling distribution and standard errors
  • Interpretation of CI
  • If sampling distribution is normal, the general formula for creating a 95% C.I.

• Regression
  • Regression line is best fitting line in what sense?
  • Interpret ALL regression table outputs
  • Study residuals
  • Categorical variables
  • Multiple Regression

So far we've seen simple linear regression

• Simple means only one predictor/independent variable \(x\)
• Outcome/depedendent variable \(y\)
• \(x\) can be either numerical or categorical

In Lec 36 LC we saw the relationship between \(x =\) dep delay & \(y =\) arr delay for Alaska Airlines flights.

• Since we only have Alaska flights, the variable carrier doesn't vary.
• But now let's also consider Frontier Airlines (carrier == F9)

So we have:

• \(y =\) arrival delay
• \(x_1 =\) departure delay (numerical variable)
• \(x_2 =\) carrier (categorical variable with \(k=2\) levels. In other words, carrier now varies.)

Is there a difference in delays between Alaska and Frontier?

Is there a difference in delays between Alaska and Frontier?

• Continuing Regression Outputs: Lec36 Learning Check
• Categorical Predictors

What does "best fitting line"" mean?