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Chapter 4: Q 49. (page 253)

Effects of class size Do smaller classes in elementary school really benefit students in areas such as scores on standardized tests, staying in school, and going on to college? We might do an observational study that compares students who happened to be in smaller and larger classes in their early school years. Identify a lurking variable that may lead to confounding with

the effects of small classes. Explain how confounding might occur.

Short Answer

Expert verified

For example, the type of school (public/private).

Step by step solution

01

Given information

We must find a variable that may cause confounding with small-class effects and determine how confounding occurs.

02

Concept

A lurking variable is one that is not included in the study's explanatory or response variables but has the potential to influence the response variable.

03

Explanation

One potential hidden factor is the private vs. public school debate. Students at private schools may have classes and receive higher grades. There should be more about private schools: they contribute to performance rather than just having tiny class sizes.

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