A Public Health Researcher Wants to Use Regression to Predict $\quad y =$

question 5

Multiple Choice

A public health researcher wants to use regression to predict the sun safety knowledge of pre-school children. The researcher randomly sampled 35 preschoolers, assigned them to one of two groups, and then measured the following three variables: SUNSCORE: $\quad y =$ Score on sun-safety comprehension test
READING: $\quad \mathrm { x } _ { 1 } =$ Reading comprehension score
GROUP: $\quad x _ { 2 } = 1$ if child received a Be Sun Safe demonstration, 0 if not
The following two models were hypothesized:
Model 1: $E ( y ) = \beta _ { 0 } + \beta _ { 1 } x _ { 1 } + \beta _ { 2 } x _ { 1 } { } ^ { 2 } + \beta _ { 3 } x _ { 2 } + \beta _ { 4 } x _ { 1 } x _ { 2 } + \beta _ { 5 } x _ { 1 } { } ^ { 2 } x _ { 2 }$
Model 2: $\mathrm { E } ( \mathrm { y } ) = \beta _ { 0 } + \beta _ { 1 } \mathrm { x } _ { 1 } + \beta _ { 3 } x _ { 2 } + \beta _ { 4 }x _ { 1 } x _ { 2 }$ A partial f-test was conducted to compare the two models and the resulting p-value was found to be 0.0023. Fill in the blank. The results lead us to conclude that there is (at ? = 0.05) .

• A) sufficient evidence of interaction between sun-safety score and reading score.
• B) sufficient evidence of a quadratic relationship between sun-safety score to reading score.
• C) insufficient evidence of quadratic relationship between sun-safety score to reading score.
• D) sufficient evidence of a statistically useful model for sun-safety score.

Calculate and understand the significance of the contribution margin and contribution margin ratio.

Understand the effect of changes in sales volume on costs and profitability.

Determine the operating income under different sales and cost scenarios.

Analyze the impact of changes in fixed and variable costs on the break-even point.

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Definitions:

Lot Size

The quantity of items that are processed, ordered, or produced as a single batch or unit.

Cycle Inventory

The average inventory maintained to meet expected demand between replenishments, reflecting the frequency of orders and volume.

Lot Size

The quantity of units produced or purchased in a single production run or order to capture economies of scale or meet demand.

Volume-Based Discount

A pricing strategy where the price per unit of goods decreases as the quantity purchased increases, designed to encourage larger orders.