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 x̅ = 23.3 with s2 = 16. Based on this sample (and using a two-tailed test with α = .01), has there been a significant change in the average level of anxiety since the 1950s? The calculated statistics for this research study are as follows: With df = 15, the critical values are t = ±2.947. For these data, the sample variance is s2 = 16, the estimated standard error is sM = 1, and t = 8.20; Cohen’s d = 2.05. a) Using a two-tailed test with α = .01, draw an appropriate conclusion about the null hypothesis and whether or not there has been a significant change in the level of anxiety over the past 50 years. b) Write a sentence that demonstrates the outcome of the hypothesis test, and the effect size, would appear in a research report. (Put more simply, write a sentence spelling out the conclusions drawn about the research question, based on this sample, and include the relevant statistics – df, calculated t-statistic, p-value, and effect size.)

Name: Standardized measures seem to indicate that the average level of anxie
Uploaded: 2024-03-20T07:07:12.000Z
Channel: Bartleby
Description: 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 ch

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

See similar textbooks

Related questions

Topic Video

Question

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 x̅ = 23.3 with

s² = 16. Based on this sample (and using a two-tailed test with α = .01), has there been a significant change in the average level of anxiety since the 1950s?

The calculated statistics for this research study are as follows:

With df = 15, the critical values are t = ±2.947. For these data, the sample variance is s² = 16, the estimated standard error is s_M = 1, and t = 8.20; Cohen’s d = 2.05.

a) Using a two-tailed test with α = .01, draw an appropriate conclusion about the null hypothesis and whether or not there has been a significant change in the level of anxiety over the past 50 years.

b) Write a sentence that demonstrates the outcome of the hypothesis test, and the effect size, would appear in a research report. (Put more simply, write a sentence spelling out the conclusions drawn about the research question, based on this sample, and include the relevant statistics – df, calculated t-statistic, p-value, and effect size.)

Definition Definition Measure of central tendency that is the average of a given data set. The mean value is evaluated as the quotient of the sum of all observations by the sample size. The mean, in contrast to a median, is affected by extreme values. Very large or very small values can distract the mean from the center of the data. Arithmetic mean: The most common type of mean is the arithmetic mean. It is evaluated using the formula: μ = 1 N ∑ i = 1 N x i Other types of means are the geometric mean, logarithmic mean, and harmonic mean. Geometric mean: The nth root of the product of n observations from a data set is defined as the geometric mean of the set: G = x 1 x 2 ... x n n Logarithmic mean: The difference of the natural logarithms of the two numbers, divided by the difference between the numbers is the logarithmic mean of the two numbers. The logarithmic mean is used particularly in heat transfer and mass transfer. ln x 2 − ln x 1 x 2 − x 1 Harmonic mean: The inverse of the arithmetic mean of the inverses of all the numbers in a data set is the harmonic mean of the data. 1 1 x 1 + 1 x 2 + ...

Expert Solution

Trending now

This is a popular solution!

Step by step

Solved in 3 steps

SEE SOLUTION Check out a sample Q&A here

Knowledge Booster

$Hypothesis Tests and Confidence Intervals for Means$

Learn more about

Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, statistics and related others by exploring similar questions and additional content below.

Similar questions