Question 1

Best Fit LineIn what sense is the regression line the straight line that "best" fits the pointsin a scatterplot?

Group of answer choices

The best-fit line connects all the dots on a scatterplot, making it a best-fit line

The best fit line draws a line that runs through 3 of the points in the data set: the lowest point, the middle point, and the highest point.

The best fit line is the line drawn so that there is minimal distance between it and all the points.

Question 2

Notation: What is the difference between

equation #1:y=0+1x

and

equation #2: y^=b0+b1x ?

Group of answer choices

There is no difference between them.

Equation #1 is based on unknown population values while equation #2 is based on sample values.

Equation #1 is based on sample values and equation #2 is based on unknown population values.

Question 3

Cereal Killers. The amounts of sugar (grams of sugar per gram of cereal) and calories (pergram of cereal) were recorded for a sample of 16 different cereals. The linear correlation coefficientisr= 0.765 and the regression equation is y^=3.46+1.01x, wherexrepresents the amount ofsugar. The mean of the 16 amounts of sugar is 0.295 grams and the mean of the 16 calorie counts is3.76. What is the best-predicted calorie count for a cereal with a measured sugar amount of 0.40 g?

Question 4

Regression EquationBelowis a data set from "graphs in Statistical Analysis," by F.J.Anscombe,The American Statistician, Vol. 27. For this data set:

X	7	5	10	8	13	9	11	14	6	4	12
Y	6.42	5.73	7.46	6.77	12.74	7.11	7.81	8.84	6.08	5.39	8.15

Follow the steps below to find the linear regression equation for the data(using TI-83/84 Plus):

1. Press STAT & choose TESTS & select LinRegTTest & Press ENTER

2. Make sure that Xlist is L1. (Assuming you entered the data for x in L1)

3. Make sure that Ylist is L2. (Assuming you entered the data for y in L2)

4. Make sure Freq is 1.

5.For the & highlight the 0 choice

6. Select "Calculate" and press ENTER.

The second line shows the regression equation with the format of

y=a+bx. Theresult will beinthe values of "a" and "b" where "a" represents the y-intercept and"b" represents the slope of the line.

Choose the correct predicted linear regression linebelow, rounding the slope and y-intercept to the nearest tenth.(Note: As these are sample values, all the answers below should have "hats" over the y values. This is a limitation in the program.)

Group of answer choices

y = 0.50 + 3x

y = 3 + 0.50x

y = 1.236 + 0.499x

y = 0.499+ 1.236

Question 5

Blood PressureMeasurementsListed below are systolic blood pressure measurements(mmHg)obtainedfrom the same woman (based on data from "Consistency of Blood PressureDifferences Between the Left and Right Arms," by Eguchi, et al.,Archives of Internal Medicine,Vol.167).

Right	102	101	94	79	79
Left	175	169	182	146	144

Find the linear regression equation. The instructions below walk you through how to find itusing aTI-83/84 Plus. You are welcome to use other forms of technology as well.

Follow the steps below to find the linear regression equation for the data(using TI-83/84 Plus):

1. Press STAT & choose TESTS & select LinRegTTest & Press ENTER

2. Make sure that Xlist is L1. (Assuming you entered the data for x in L1)

3. Make sure that Ylist is L2. (Assuming you entered the data for y in L2)

4. Make sure Freq is 1.

5.For the & highlight the 0 choice

6. Select "Calculate" and press ENTER.

The second line shows the regression equation with the format of

y=a+bx. Theresult will beinthe values of "a" and "b" where "a" represents the y-intercept and"b" represents the slope of the line.

Enter the predicted linear regression linebelow, rounding the slope and y-intercept to the nearest hundredth.

y^= [ Select ] ["3.01", "0.06", "43.56", "1.31"] + [ Select ] ["3.01", "0.06", "43.56", "1.31"] x