Instruction 13.21 A Weight-Loss Clinic Wants to Use Regression Analysis to Build

question 107

Multiple Choice

Instruction 13.21
A weight-loss clinic wants to use regression analysis to build a model for weight-loss of a client (measured in kilograms) . Two variables thought to effect weight-loss are client's length of time on the weight loss program and time of session. These variables are described below:
Y = Weight-loss (in kilograms)
X₁ = Length of time in weight-loss program (in months)
X₂ = 1 if morning session, 0 if not
X₃ = 1 if afternoon session, 0 if not (Base level = evening session)
Data for 12 clients on a weight-loss program at the clinic were collected and used to fit the interaction model:
Y = β0 + β₁X₁ + β₂X₂ + β₃X₃ + β₄X₁X₂ + β₅X₁X₃ + ε
Partial output from Microsoft Excel follows:

-In a multiple regression model,the adjusted r²

• A) can sometimes be negative.
• B) can sometimes be greater than +1.
• C) cannot be negative.
• D) has to fall between 0 and +1.

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Definitions:

Plasma Cells

A type of white blood cell that produces antibodies in response to infections.

Lymphocytes

A type of white blood cell central to the immune system, responsible for antibody production and other defense mechanisms against infection and disease.

Lymph Nodes

Small, bean-shaped structures that are part of the lymphatic system, serving as filters for harmful substances and a site for immune cell activation.

Lymphoid Cells

Cells that are part of the immune system, including B cells, T cells, and natural killer cells, which play roles in adaptive and innate immunity.