Question

Normalization is the process that makes the numerical data independent of scale.

True or False

TrueFalse

In excel, to construct a residual plot, input of a y range and an x range is needed. Aimee is examining the relationship between age and square foot range (sqft) of living space. In the scenario provided, what would be the y and what would be the x range data?

Multiple Choice

• In selecting a regression, residual plot is the first selection before range input.

• Input y range would be age and Input x range would be sqft.

• Input y range would be blank to produce a concise x range.

• Input y range would be sqft and Input x range would be age.

In the model y = β₀ + β₁x + ε, the predicted value is yˆy^ = b₀ + b₁x. What is the impact of the estimated slope coefficient?

Multiple Choice

• b₁ measures the approximate change in yˆy^ when x increases by 1 unit.

• b₁ × 0.01 measures the approximate change in yˆy^ when x increases by 1%.

• b₁ measures the approximate change in yˆy^ when x increases by 1%.

• b₁ × 100 measures the approximate change in yˆy^ when x increases by 1 unit.

Molly emailed her clients offering a free 30-minute massage for referrals. In the following validation set of 100, class 1 reflects the clients predicted to provide referrals and class 0 reflects the clients predicted to not provide referrals. Based on the confusion matrix, what was the False Negative (FN) of current clients who provided referrals for a free message?

Actual Class	Predicted Class 1	Predicted Class 0
Class 1	18	11
Class 0	11	60

Multiple Choice

• 29

• 18

• 11

• 60

Todd uses the quadratic regression model to determine the predictive average unit cost of baseballs produced in his production facility. After determining predictive average costs at multiple unit batch size amounts in millions, he now wants to know what the output level that minimizes his costs would be. Given b₁ = −0.3904 and b₂ =0.0247, what is the level that will maximize his average cost in units?

Multiple Choice

• 7.2 million units

• 2.8 million units

• 20.40 million units

• 7.90 million units

Answer 1

1) False. Normalization is the process that makes the numerical data standardized or neutral scale not independent of scale.

2) True. In excel to construct a residual plot x and y are needed. However, the actual plot is between the residuals and the predicted values.

3) In input y is sqft and x is age.

4) b1 is the approximate change in yhat when x increases by 1 unit.

5) The quadratic equation is:

y = a + b1*x + b2*x^2

Differentiating with respect to x and equating to zero we get

-b1=2*b2*x

or x = 7.9 million units.