Three Examples of Testing a Single Mean

Slides:



Advertisements
Similar presentations
Introduction to Hypothesis Testing
Advertisements

The Proper Conclusion to a Significance Test. Luke Wilcox is an “acorn” at the 2013 AP Statistics reading. After three days of scoring, his table leader.
Choosing Significance Level Section Starter At the local bakery, loaves of bread are supposed to weigh 1 pound, with standard deviation 0.13.
© 2010 Pearson Prentice Hall. All rights reserved Two Sample Hypothesis Testing for Means from Independent Groups.
© 2001 Prentice-Hall, Inc.Chap 9-1 BA 201 Lecture 15 Test for Population Mean Known.
Chapter 8 Inference for Proportions
Chapter 9 Hypothesis Testing Testing Hypothesis about µ, when the s.t of population is known.
Fundamentals of Hypothesis Testing. Identify the Population Assume the population mean TV sets is 3. (Null Hypothesis) REJECT Compute the Sample Mean.
Hypothesis Testing Steps of a Statistical Significance Test. 1. Assumptions Type of data, form of population, method of sampling, sample size.
Chapter 9 Hypothesis Testing 9.4 Testing a Hypothesis about a Population Proportion.
Chapter 6 Inference for a Mean
Hypothesis Testing Sample Means. Hypothesis Testing for Sample Means The goal of a hypothesis test is to make inferences regarding unknown population.
Business Statistics - QBM117 Testing hypotheses about a population mean.
Significance Tests for Proportions Presentation 9.2.
Hypothesis Testing. What is a Hypothesis In statistics, a hypothesis is a claim or statement about a characteristic of a population. A Null Hypothesis,
Confidence Intervals and Hypothesis Testing - II
CHAPTER 2 Statistical Inference 2.1 Estimation  Confidence Interval Estimation for Mean and Proportion  Determining Sample Size 2.2 Hypothesis Testing:
Jump to first page HYPOTHESIS TESTING The use of sample data to make a decision either to accept or to reject a statement about a parameter value or about.
Claims about a Population Mean when σ is Known Objective: test a claim.
1 Introduction to Hypothesis Testing. 2 What is a Hypothesis? A hypothesis is a claim A hypothesis is a claim (assumption) about a population parameter:
Section 9.2 Testing the Mean  9.2 / 1. Testing the Mean  When  is Known Let x be the appropriate random variable. Obtain a simple random sample (of.
Section 10.3: Large-Sample Hypothesis Tests for a Population Proportion.
Significance Test A claim is made. Is the claim true? Is the claim false?
Comparing Two Means and Two Standard Deviations Module 23.
Lecture 16 Section 8.1 Objectives: Testing Statistical Hypotheses − Stating hypotheses statements − Type I and II errors − Conducting a hypothesis test.
Introduction to Inferece BPS chapter 14 © 2010 W.H. Freeman and Company.
HAWKES LEARNING SYSTEMS Students Matter. Success Counts. Copyright © 2013 by Hawkes Learning Systems/Quant Systems, Inc. All rights reserved. Example 10.17:
Tests of Significance: The Basics BPS chapter 15 © 2006 W.H. Freeman and Company.
Chapter 12: Hypothesis Testing. Remember that our ultimate goal is to take information obtained in a sample and use it to come to some conclusion about.
9.1 Notes Introduction to Hypothesis Testing. In hypothesis testing there are 2 hypothesis for each problem, the null hypothesis and the alternate hypothesis.
Hypothesis Testing Errors. Hypothesis Testing Suppose we believe the average systolic blood pressure of healthy adults is normally distributed with mean.
What is a Test of Significance?. Statistical hypotheses – statements about population parameters Examples Mean weight of adult males is greater than 160.
STEP BY STEP Critical Value Approach to Hypothesis Testing 1- State H o and H 1 2- Choose level of significance, α Choose the sample size, n 3- Determine.
C HAPTER 4  Hypothesis Testing -Test for one and two means -Test for one and two proportions.
Matched Pairs t-test Module 22a. Matched Pairs t-test To this point we have only looked at tests for single samples. Soon we will look at confidence intervals.
Testing a Single Mean Module 16. Tests of Significance Confidence intervals are used to estimate a population parameter. Tests of Significance or Hypothesis.
Hypothesis Testing. Suppose we believe the average systolic blood pressure of healthy adults is normally distributed with mean μ = 120 and variance σ.
Chapter 9: Hypothesis Tests for One Population Mean 9.2 Terms, Errors, and Hypotheses.
© 2010 Pearson Prentice Hall. All rights reserved Chapter Hypothesis Tests Regarding a Parameter 10.
Chapter 10 Inference on Two Samples 10.3 Inference About Two Population Proportions.
Parameter Estimation.
Tests of Significance: The Basics
Topics: Essentials Hypotheses Testing Examples
Chapter 7 Hypothesis Testing with One Sample.
Properties of Normal Distributions
One sample Tests & Intervals on the Calculator
Chapter 9 Hypothesis Testing
Chapter 20 MATH 2400.
One sample t-test and z-test
MATH 2311 Week 14 (Test 3 Review).
اختبار الفرضيات اختبارالفرضيات المتعلقة بالوسط
Topics: Essentials Hypotheses Testing Examples
Chapter 9 Hypothesis Testing
Chapter 9 Hypothesis Testing
Elementary Statistics: Picturing The World
Chapter 7 Hypothesis Testing with One Sample.
Confidence Interval Construction
Hypothesis Testing (Cont.)
Defining the null and alternative hypotheses
LESSON 20: HYPOTHESIS TESTING
Hypothesis Tests One Sample Means
Tests About a Population Mean
Chapter 9 Hypothesis Testing
Tests About a Population Mean
Chapter 11: Testing a Claim
More on Testing 500 randomly selected U.S. adults were asked the question: “Would you be willing to pay much higher taxes in order to protect the environment?”
Section 8.1 Additional Popper #34: Choice A for #1 – 10
Chapter 9 Hypothesis Testing: Single Population
Hypothesis Testing for Proportions
Hypothesis Testing 1 Copyright by Winston S. Sirug, Ph.D.
Presentation transcript:

Three Examples of Testing a Single Mean Module 17

Three Examples of Significance Tests Example 1: Arsenic “A factory that discharges waste water into the sewage system is required to monitor the arsenic levels in its waste water and report the results to the Environmental Protection Agency (EPA) at regular intervals. Sixty beakers of waste water from the discharge are obtained at randomly chosen times during a certain month. The measurement of arsenic is in nanograms per liter for each beaker of water obtained.” (from Graybill, Iyer and Burdick, Applied Statistics, 1998). Suppose the EPA wants to test if the average arsenic level exceeds 30 nanograms per liter at the 0.05 level of significance.

Three Examples of Significance Tests Arsenic Example Information given: 37.6 56.7 5.1 3.7 3.5 15.7 20.7 81.3 37.5 15.4 10.6 8.3 23.2 9.5 7.9 21.1 40.6 35 19.4 38.8 20.9 8.6 59.2 6.2 24 33.8 21.6 15.3 6.6 87.7 4.8 10.7 182.2 17.6 152 63.5 46.9 17.4 26.1 21.5 3.2 45.2 12 128.5 23.5 24.1 36.2 48.9 16.5 33.2 25.6 33.6 12.2 9.9 14.5 30 Sample size: n = 60. Assume it is known that s = 34.

Three Examples of Significance Tests Arsenic Example 1. State the null hypothesis: 2. State the alternative hypothesis: 3. State the level of significance

Three Examples of Significance Tests Arsenic Example 4. Calculate the test statistic. 5. Find the P-value.

Three Examples of Significance Tests Arsenic Example 6. Do we reject or fail to reject H0 based on the P-value? 7. State the conclusion.

Three Examples of Significance Tests Example 2: Cereal “An operator of cereal-packaging machine monitors the net weights of the packaged boxes by periodically weighing random samples of boxes…One condition required for the proper operation of the machine is that the mean is 453 grams.” (from Graybill, Iyer and Burdick, Applied Statistics, 1998). The operator wishes to see if a random sample of 50 boxes gives evidence that the mean is different than 453 grams.

Three Examples of Significance Tests Cereal Example Information given:

Three Examples of Significance Tests Cereal Example 1. State the null hypothesis: 2. State the alternative hypothesis: 3. State the level of significance

Three Examples of Significance Tests Cereal Example 4. Calculate the test statistic. 5. Find the P-value.

Three Examples of Significance Tests Cereal Example 6. Do we reject or fail to reject H0 based on the P-value? 7. State the conclusion.

Three Examples of Significance Tests Example 3: Salary A state representative wants to know the mean salary for the faculty at a state university in her district. She recently read a newspaper article that stated the mean salary for faculty in state universities is $51,000. At present, the representative does not plan to support any bill that would increase faculty salaries at the university. However, if she can be convinced that the mean salary of the faculty is less than $51,000, she will support such a bill. The representative asked an intern to select a simple random sample of 25 faculty from the list of faculty in the university catalog and use these salaries to conduct a statistical test using a = 0.025 (adapted from Graybill, Iyer and Burdick, Applied Statistics, 1998).

Three Examples of Significance Tests Salary Example Information given:

Three Examples of Significance Tests Salary Example 1. State the null hypothesis: 2. State the alternative hypothesis: 3. State the level of significance

Three Examples of Significance Tests Salary Example 4. Calculate the test statistic. 5. Find the P-value.

Three Examples of Significance Tests Salary Example 6. Do we reject or fail to reject H0 based on the P-value? 7. State the conclusion.