An English Teacher Has Been Teaching a Sixth Grade Composition

question 75

Multiple Choice

An English teacher has been teaching a sixth grade composition class for many years. He has the feeling that over the past several years, the writing ability of students has changed. A national test of proficiency in composition was administered 5 years ago. The resulting distribution of scores was normally shaped, had a mean of 85 and a standard deviation of 10.9. In order to test his feeling, he gives his present class of 43 students the same proficiency test. The resulting mean is 80 and the standard deviation is 8.7. The obtained value of the appropriate statistic for testing H 0 is _________.

• A) z obt = - 0.46
• B) z obt = +3.01
• C) z obt = - 3.01
• D) z obt = - 0.45

---

Definitions:

Fitted Values

Estimated values predicted by a regression model, based on the observed data.

Simple Linear Regression

A statistical method that models the linear relationship between a dependent variable and one independent variable by fitting a linear equation to observed data.

SAT Exam

A standardized test widely used for college admissions in the United States, assessing reading, writing and language, and mathematics skills.

Grade Point Average

The average result of all the grades achieved throughout a course, calculated by assigning a numerical value to each grade and then averaging these values.