Your Textbook Extends the Simple Regression Analysis of Chapters 4 $\widehat{\text { TestScore }}$

question 41

Essay

Your textbook extends the simple regression analysis of Chapters 4 and 5 by adding an additional explanatory variable, the percent of English learners in school districts (PctEl). The results are as follows: $\widehat{\text { TestScore }}$ = 698.9 - 2.28 × STR
and $\widehat{\text { TestScore} }$ = 698.0 - 1.10 × STR - 0.65 × PctEL
Explain why you think the coefficient on the student-teacher ratio has changed so dramatically (been more than halved).

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Definitions:

Cephalocaudal Development

A development pattern in which growth starts at the head and moves down towards the body.

Proximodistal

Describes the pattern of development in children where growth starts at the center of the body and moves towards the extremities.

Central Axis

An imaginary line that is central to an object or structure, providing a point of symmetry or balance.

Axon

A long, slender projection of a nerve cell that typically conducts electrical impulses away from the neuron's cell body.