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Chapter 3: Q.43 (page 191)

Least-squares idea The table below gives a small set of data. Which of the following two lines fits the data better: y^=1−xory^=3−2x? Make a graph of the data and use it to help justify your answer. (Note: Neither of these two lines is the least-squares regression line for these data.)

Short Answer

Expert verified

The lineY∧=3-2fits the data better.

Step by step solution

01

Given Information

It is given in the question that,y^=1−xory^=3−2x

02

Explanation

Below is the scatter plot for the data given,

By using a red line, the line Y∧=1-Xcan be seen and by using a green line, it can be seen that Y∧=3-2Xcan be seen.

The figure shows that lineY∧=1-Xfits better in a scatter plot since it passes through only two points and that the rest of the points follow this line closely.

The data is, therefore, better suited toY∧=3-2X.

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