Statistics for Business: Decision Making and Analysis, 3rd Edition

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1. 33. Walmart

   1. No. Net income is growing at a growing rate.

   2. b₀ = − 378,964 million dollars is a huge extrapolation. b₁ = $190 million/year is the overall constant rate of growth.

   3. The data bend, with increasing seasonal variation over time.

   4. Closer to linear, but with a slight downward curve remaining.

   5. b₀ = − 241 million dollars remains an extrapolation. b₁ = 0.124 is the annual percentage rate of growth (12.4%).

   6. Some curvature, with an evident seasonal pattern (sales higher in fourth quarter).

   7. Transformed equation captures overall growth better as indicated by the higher r².

2. 35. Wine

   1. The relationship seems linear, though the floor of prices at zero complicates the analysis.

   2. Estimated Price = − 1058.588 + 12.18428 Rating with r² = 0.55. ...