Standardized measures seem to indicate that the average level of anxiety has increased gradually over the past 50 years (Twenge, 2000). In the 1950s the average score on the Child Manifest Anxiety Scale was µ=15.1. A sample of n=16 of today's children produces a mean score of M=23.3 with a SS=240 (sum of squares). a. Based on the sample, has there been a significant change in the average level of anxiety since the 1950s? use a two-tailed test with a=.01. b. Make a 90% confidence interval estimate of today's population mean level of anxiety. Write a sentence that demonstrates how the outcome of the hypotheses test and confidence interval might appear in a research study. C.

Standardized measures seem to indicate that the average level of anxiety has increased gradually over the past 50 years (Twenge, 2000). In the 1950s the average score on the Child Manifest Anxiety Scale was µ=15.1. A sample of n=16 of today's children produces a mean score of M=23.3 with a SS=240 (sum of squares). a. Based on the sample, has there been a significant change in the average level of anxiety since the 1950s? use a two-tailed test with a=.01. b. Make a 90% confidence interval estimate of today's population mean level of anxiety. Write a sentence that demonstrates how the outcome of the hypotheses test and confidence interval might appear in a research study. C.

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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