1. Warm Up
Work with your table and list at least 5 things you remember from Chapter 3, which was about correlation and linear regression. These could be definitions, formulas, calculator functions or other important ideas.

2. Example
Imagine we have data from a random set of college freshmen comparing their SAT score to their freshman GPA.
SAT GPA SAT GPA
Find the equation of the LSRL and the value of r for this data.

3. Practice #1
This study investigated the survival rate of those who received a defibrillator shock after suffering cardiac arrest. The first row is the time (in min) between an individual going into cardiac arrest and receiving the shock. The second row shows the percentage who survived.
Time
Survival
1) Find the LSRL and the correlation coefficient.
2) Interpret the slope and y-intercept in context.
3) Estimate the survival rate for a time of 5 minutes.

4. Practice #2
In a 2010 study, three short clips from a popular song (each 0.4 seconds long) were played for 23 college students with musical training. The students were asked to identify the year the song was released. The average of the students’ guesses is shown versus the actual year of release.
Actual Guess Actual Guess Actual Guess
1) Find the equation of the LSRL and the value of r.
2) What is the meaning of the slope and y-intercept in the context of the problem.
3) Plot the residuals and comment on its meaning.

5. Is there a linear correlation between number of words found in a word search and time?
1) Everyone will be given a word search puzzle.
2) You will be randomly assigned from 1 to 6 minutes to find as many words as possible. This will be done by drawing a card from Ace to 6.
3) When instructed to begin, find as many words as possible in the word search. Stop when your time is up.

6. Is there a linear correlation between number of words found in a word search and time?
1) Exchange your word search with someone else at your table.
2) Check how many correct words were found. The word must be on the list and spelled correctly in the word search. Return the word search to its owner.
3) Write your data on the board as an ordered pair (time, words found).

7. Is there a linear correlation between number of words found in a word search and time?
1) Enter the time in L1 and the number of words in L2.
2) Make a scatterplot and comment on it (don’t need to copy it)
3) Calculate the correlation coefficient r and the LSRL.
4) Make a plot of the residuals.
5) Do you think a linear model is suitable for the correlation between time and number of words? Why or why not?
6) Using the LSRL, estimate the number of words a student would find in 7 minutes. Do you think this is a good estimate? Why or why not?