TABLE 13-11 A Weight-Loss Clinic Wants to Use Regression Analysis to Build

question 159

Multiple Choice

TABLE 13-11
A weight-loss clinic wants to use regression analysis to build a model for weight loss of a client (measured in pounds) . Two variables thought to affect 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 pounds)
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:

-Referring to Table 13-11, in terms of the βs in the model, give the mean change in weight loss (Y) for every one-month increase in time in the program (X₁) when attending the morning session.

• A) β₁ + β₄
• B) β₁ + β₅
• C) β₁
• D) β₄ + β₅

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Definitions:

Carbon Monoxide Poisoning

A potentially fatal condition caused by inhaling carbon monoxide gas, leading to symptoms such as headache, dizziness, and nausea, due to reduced oxygen carrying capacity of blood.

Smoke Inhalation

The act of breathing in combustion products during exposure to fire, which can lead to respiratory distress and other health issues.

Pulse Oximetry

A non-invasive method to monitor the oxygen saturation level of the blood using a device usually clipped to a finger.

Arterial Blood Gases

Tests that measure the levels of oxygen and carbon dioxide in the arterial blood, indicating the efficiency of the lungs in gas exchange.