The Following Results Were Obtained from a Multiple Regression Analysis

question 109

Essay

The following results were obtained from a multiple regression analysis of supermarket profitability. The dependent variable, y, is the profit (in thousands of dollars) and the independent variables, x₁ and x₂, are the food sales and nonfood sales (also in thousands of dollars). Coefficient of determination = 0.7139
a.Write the estimated regression equation for the relationship between the variables.
b.What can you say about the strength of this relationship?
c.Carry out a test of whether y is significantly related to the independent variables. Use a .01 level of significance.
d.Carry out a test of whether x₁ and y are significantly related. Use a .05 level of significance.
e.How many supermarkets are in the sample used here?

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Definitions:

Decomposition

The process by which organic substances are broken down into simpler forms of matter, often involving the action of bacteria and fungi.

Primary Producers

Organisms, usually plants and algae, that can produce their own food through photosynthesis, forming the base of the food web.

Headwater Streams

The upper tributaries of a river system, crucial for maintaining the health of the entire ecosystem.