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Hypothesis Testing

Statistics: Hypothesis Testing for Mean and Variance Problem Set

1. At the time she was hired as a server at the Grumney Family restaurant, Beth Brigden was told, "You can average more than $20 a day in tips." Over the first 35 days she was employed at the restaurant, the mean daily amount of her tips was $24,85, with a standard deviation of $3.24. Can Ms. Brigden be 99% confident that

Advice on Drafting a Problem Statement

Here is the assignment: · Submit a draft of two problem statements that address current situations, issues, or observations in your field of study (Human Resources) or discipline to your individual forum. Back each of the problems with at least two recent sources from peer reviewed journals (within the past 5 years). Each p

5 step hypothesis

Domestic Imported t-Test: Two-Sample Assuming Equal Variances 23.197 20.454 23.372 26.651 Domestic Imported 23.591 27.453 Mean 25.8462 21.64134 30.872 17.266 Variance 18.3941306 12.91803027 19.587 18.021 Observations 30 50 23.169 28.683 Pooled Variance 14.9540163 35.851 19.251 Hypothes

Correlation coefficient & 7-step hypothesis test

In order for applicants to work for the state department, they must take a test in the language of the country where they plan to work. The data below shows the relationship between the number of years that applicants have studied a particular language and the grades they received on the proficiency exam. Applicant # 1 2 3 4

Two questions: variances

1] For the samples summarized below, test the hypothesis at = 0.5 that the two variances are equal. Sample 1 Variance = 25 Number of data values = 9 Sample 2 Variance = 9 Number of data values = 19 Do we reject or not reject and why 2] A marketing firm asked a random set of mar

ANOVA;analysis of variance, etc

1. To determine if a diet supplement is useful for increasing weight, patients are weighed at the start of the program and at the end of the program. This is an example of a. test of paired differences. b. independent sample. c. one-sample test for means. d. two-sample test for means. 2. The analysis of variance tech

Just need a mapping

I downloaded all of the problems separately and just need a mapping into the instructors grading key, Can someone please help with this? I think there is one problem without a solution. And I really need the formulas spelled out so I can replicate them. Thanks

Regional Differences in Household Savings

For items 1 to 4, select the best statistical analysis technique for the following research topics. Be very precise about your statistical choice. For example, there are several types of t-tests, correlations, and ANOVA tests. Make sure you specify exactly which statistical analysis technique you would use, e.g. One-Way Anova

Z tests & t tests

1. If two independent samples are used in a hypothesis test concerning the difference between population means for which the combined degrees of freedom is 20, which of the following could not be true about the sample sizes n1 and n2? A) n1=12 and n2=8 B) n1=12 and n2=10 C) n1=13 and n2=9 D) Cannot be determined from the giv

Proportion of Germinating Seeds Testing

The data presented in the table below resulted from an experiment in which seeds of 5 different types were planted and the number of seeds that germinated within 5 weeks after planting was recorded for each seed type. At the .01 level of significance, is the proportion of seeds that germinate dependent on the seed type?

Hypothesis Testing for Environmental Estimates

An environmentalist estimates that the more waste recycled by adults in the country is more than 1 pound per person per day. You want to test this claim. You find that the mean waste recycled per person per day for a random sample of 9 adults in the country is 2 pounds and the standard deviation is 0.3 pound. At a = 0.10, can

Null hypothesis

State whether the standardized test statistic Z indicate that you show reject the null hypothesis. Choose correct answer. Ho = 1.645 1. For Z = 1.659, should you reject or fail to reject the null hypothesis: a) Fail to reject Ho because Z > 1.645 b) Reject Ho because Z < 1.645 c) Fail to reject Ho because Z < 1

Hypothesis Testing for a Chess Club Claims

A local chess club claims that the length of time to play a game has a mean of 49 minutes or more. Write sentences describing type I and type II errors for a hypothesis test o this claim. A Type I error will occur if the actual mean of the length of time to play a game is "pick one to insert in sentence" (less than, equal t

Hypothesis Testing

A random sample of 81 eighth grade students scores on a national mathematics assessment test has a mean score of 286 with a standard deviation of 32. This test result prompts a state school administrator to declare that the mean score for the states eighth graders on this exam is more than 280. At a=0.04, is there enough evide

Hypothesis Testing for Medical Researchers

A medical researcher says that at least 29% of adults are smokers. In a random sample of 198 adults, 22.7% say they are smokers. At a=0.03, do you have enough evidence to reject the research claim? a) What is the critical value? Zo = b) Identify the standardized test statistic? Z = c) Decide whether to reje

Hypothesis Testing Comparison

No hypothesis need. 2 population comparison with populations less than 30 Calculate the following at a .05 level of significance: Population 1 Population 2 Sample size n1 = 25 n2 = 20 Sample mean xbar1 = 22.3 xbar2 = 18.5 Sample st. dev s1 = 1.5 s2 = 2.2

Solutions for Hypothesis Testing

1. In Meijer supermarket, the customer's waiting time to check out is approximately normally distributed with a standard deviation of 2.5 minutes. A sample of 25 customer waiting times produced a mean of 8.2 minutes. Is this evidence sufficient to reject the supermarket's claim that its customer checkout time averages no more th

Hypothesis Testing for Mean (Small Samples)

Hypothesis Testing for Mean (Small Samples) 1. A local tire store suspects that the mean life of a new discount tire is less that 39,000 miles. To check the claim, the store selects randomly 18 of these new discount tires. When they are tested, it is found that the mean life is 38,250 miles with a sample standard deviation s

Hypothesis Testing for the Mean (Large Samples)

Hypothesis Testing for the Mean (Large Samples) 1. Use the method specified to perform the hypothesis test for the population mean . WeatherBug say that the mean daily high for December in a large Florida cit is F. WFLA weather suspects that this temperature is not accurate. A hypothesis test is performed the determine

Introduction to Hypothesis Testing

Introduction to Hypothesis Testing State the claim mathematically. Then write the null and alternative hypothesis. Determine whether the hypothesis test is left-tailed, right-tailed, or two-tailed. a. A research hospital claims that more than 3.7% of the population suffers from high blood pressure. Use p, the represent

Applications of inference and hypothesis testing

In what areas of your business is it important to draw inference? Describe a time when drawing an inference may have hurt your business. What is the significance of a one-tailed test as opposed to a two-tailed test? Describe a set of data that is one tailed. Describe a second set that is 2 tailed.


1. A researcher wishes to test the claim that the average age of lifeguards in Ocean City is greater than 24 years. She selects a sample of 36 guards and finds the mean of the sample to be 24.7 years with a standard deviation of 2 years. Is there evidence to support her claim at a 95% level of confidence? 2. Consider the fo

Stat problem

I need answers and solution the attached questions. This is very urgent ASAP please Thank u ps: I need the answers to the following questions from the book: Statistics for managers using Microsoft excel 5th edition Problem: Question 8-67: Companies are spending more time screening applicants than in the past. A stud

5 step five hypothesis

Five Step Hypothesis Null should be: There is a difference between male and female salaries at all levels ALternate should be: There is no difference between male and female salaries at all levels. The conclusion of the parametric should be "Do Not Reject Ho" contingency table Observed Educat

Null and alternative hypothesis

Part 1 For the following investigative scenarios, state the null hypothesis, and the alternative hypothesis. Also identify the Type 1 and Type 2 errors which can result based on the hypotheses that you defined. (a) You are a member of the HR department and a number of employees have to come to you claiming tha

(Statistics) Hypothesis Testing

Testing Hypothesis. Identify the null hypothesis, alternative hypothesis, test statistics, P-value or critical value (s), conclusion about the null hypothesis, and final conclusion that address the original claim. Use the P-value method unless your instructor specifies otherwise. A random sample of 100 babies is obtained, and