Identify the rejection region for each of the following cases. Assume

v1=7andv2=9

a. Ha1222,α=.05

b. Ha1222,α=.01

c. Ha12σ22,α=.1withs12>s22

d. Ha1222,α=.025

Short Answer

Expert verified

A hypothesis is a tested assertion concerning the relation among two or more factors or a suggested reason for an observable phenomenon.

Step by step solution

01

Step-by-Step Solution Step 1: (a) Find the rejected region

The numerator degrees of freedom is v1=7

The denominator degrees of freedom is v2=9

The alternative hypothesis is Ha:σ12<σ22

The level of significance isα=0.05

As the alternative hypothesis is given to us, so we will set up a null hypothesis, that isH0:σ12=σ22

Using percentage points of the F-distributionα=0.05, the critical value is3.293

Therefore, the rejection region is F>3.293.

02

(b) Find the rejected region

The numerator degrees of freedom isv1=7

The denominator degrees of freedom isv2=9

The alternative hypothesis isHa:σ12>σ22

The level of significance isα=0.01

As the alternative hypothesis is given to us, so we will set up a null hypothesis, that is H0:σ12=σ22

Using percentage points of the F-distributionα=0.01 , the critical value is5.613

Therefore, the rejection region is F>5.613.

03

(c) Find the rejected region

The numerator degrees of freedom isv1=7

The denominator degrees of freedom isv2=9

The alternative hypothesis isHa:σ12σ22

The level of significance isα=0.1

As the alternative hypothesis is given to us, so we will set up a null hypothesis, that isH0:σ12=σ22

Using percentage points of the F-distributionα=0.1 , the critical value is2.505

Therefore, the rejection region is F>2.505.

04

(d) Find the rejected region 

The numerator degrees of freedom isv1=7

The denominator degrees of freedom isv2=9

The alternative hypothesis isHa:σ12<σ22

The level of significance isα=0.025

As the alternative hypothesis is given to us, so we will set up a null hypothesis, that isH0:σ12=σ22

Using percentage points of the F-distributionα=0.025, the critical value islocalid="1652720854474" 4.197

Therefore, the rejection region isF>4.197.

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Test and CI for two Variances: Content vs Site

Method

Null hypothesis α1α2=1

Alternative hypothesis α1α21

F method was used. This method is accurate for normal data only.

Statistics

Site N St Dev Variance 95% CI for St Devs

1 25 3.067 9.406 (2.195,4.267)

2 25 3.339 11.147 (2.607,4.645)

Ratio of standard deviation =0.191

Ratio of variances=0.844

95% Confidence Intervals

Method CI for St Dev Ratio CI Variance Ratio

F (0.610, 1.384) (0.372, 1.915)

Tests

Method DF1 DF2 Test statistic p-value

F 24 24 0.84 0.681

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