Q1)

Fitting a straight line to a set of data yields the following prediction line:

Yi = 2 + 5 Xi

(a) Interpret the meaning of the Y intercept, b0.

(b) Interpret the meaning of the slope, b1.

(c) Predict the value of Y for X = 3.

Q2)

The marketing manager of a large super market chain would like to use shelf space to predict the sales of pet food. A random sample of 12 equal-sized stores is selected, with the following results:

Shelf Space (Feet) Weekly Sales (RM)

5 160

5 220

5 140

10 190

10 240

10 260

15 230

15 270

15 280

20 260

20 290

20 310

(a) Construct a scatter plot.

(b) Assuming a linear relationship, use the least-squares method to determine coefficient b0, and b1.

(c) Predict the weekly sales of pet food for stores with 8 feet of shelf space for pet food.

Q3

In the Q2, the marketing manager used shelf space for pet food to predict weekly sales. For those data, SSR = 20,535 and SST = 30,025.

(a) Determine the coefficient of determination, r2 , and interpret its meaning.

(b) Determine the standard error of the estimate.

(c) How useful do you think this regression model is for predicting sales?

Q4

An agent for a residential real estate company in a large city would like to be able to predict the monthly rental cost for apartments, based on the size of an apartment, as defined by square footage. The agent selects a sample of 25 apartments in a particular residential neighborhood and gathers the following data.

Rent (RM) Size (Square Feet)

950 850

1600 1450

1200 1085

1500 1232

950 718

1700 1485

1650 1136

935 726

875 700

1150 956

1400 1100

1650 1285

2300 1985

1800 1369

1400 1175

1450 1225

1100 1245

1700 1259

1200 1150

1150 896

1600 1361

1650 1040

1200 755

800 1000

1750 1200

(a) Construct a scatter plot.

(b) Use the least-squares method to determine the regression coefficient b0 and b1.

(c) Interpret the meaning of b0 and b1 in this problem.

(d) Predict the monthly rent for an apartment that has 1,000 square feet.

Q5

The file contains the calories and sugar, in grams, in one serving of seven breakfast cereals:

Cereal calories sugar

Kellogg's All Bran 80 6

Kellogg's Corn Flakes 100 2

Wheaties 100 4

Nature's Path Organic 110 4

Kellogg's Rice Krispies 130 4

Post Shredded Wheat 190 11

Kellogg Mini Wheats 200 10

(a) Compute and interpret the coefficient of correlation, r.

(b) At the 0.05 level of significance, is there a significant linear relationship between calories and sugar?

please help me get the answer and I also want to know the steps in every questions