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Hypothesis Testing

Checking for Pollution

A common method of checking for pollution in a river is to measure the dissolved oxygen content in the river water at different locations. A reduction of oxygen content in the water from one location to another indicates the presence of pollution somewhere between the two locations. The Environmental Protection Agency (EPA) su

Gasoline Additive

To learn about the effect of a newly developed gasoline additive on gas mileage (mpg), seven cars were driven 300 miles first without additive and then 300 miles with a gas additive. Here are the mpg's. Did the new additive improve gas mileage? Also, is the test dependent or independent. Car # m

Hypothesis Testing: Minor Automobile Accidents

A number of minor automobile accidents occur at various high-risk intersections in Teton County despite traffic lights. The Traffic Department claims that a modification in the type of light will reduce these accidents. The county commissioners have agreed to a proposed experiment. Eight intersections were chosen at random, and

The Grand Strand Family Medical Center

The Grand Strand Family Medical Center is specifically set up to treat minor medical emergencies for visitors to the Myrtle Beach area. There are two facilities, one in the Little River Area and the other in Murrells Inlet. The Quality Assurance Department wishes to compare the mean waiting time for patients at the two locations

Research Design

1. The Dean is hanging his head in shame. He realizes his failings in designing an adequate research design to assess the effects of the move on majors and has revised the proposal. Unfortunately, the word processor used (WordImperfect) has scrambled the text and he needs help in correcting the text. In the paragraphs below, h

Two Statistics Problems

(See attached file for full problem description) --- 1. On a college bulletin, it is stated that the weights of the male students are normally distributed with mean = 165lb and a standard deviation = 16lb. A research student decided to verify the claim of the school by taking a sample of 64 students. The average weight of the

Decision Rules, Test Statistics, and Null Hypothesis

H-subzero: Pie = .40 H-subone: Pie does not equal .40 A sample of 120 observations revealed that p = .30. At the .05 significance level, can the null hypothesis be rejected? A: State the decision rule B: Compute the value of the test statistic C: What is your decision regarding the null hypothesis?

Hypothesis testing and correlation coefficient

1. A normal tomato will gain an average of 2 ounces per week during the growing season. A sample of 100 tomatoes is given a special hormone to increase their growth. The average weight gain of tomatoes in the sample was 3 ounces with a standard deviation of 1 ounce. Conduct a hypothesis test to determine if the hormone increased

2 Problems

2) Disney tells you that the average distance between the ears on a Mickey Mouse hat is 5 inches. In a sample of 100 Mickey Mouse hats you find that the average distance between the ears on the hats is 5.2 inches with a standard deviation of 1 inch. Conduct a hypothesis test to determine if the average distance between the ear

Hypothesis Testing, Null and Alternate Hypothesis and Two-Tailed Hypothesis Tests

5) ESPN reported in sample of 1000 homes the proportion of people who watched the Texas v. Ohio State college football game this weekend was .6. ESPN also reported that in another sample of 1000 homes the proportion of people who watched the Arizona State v. Louisiana State game was .4. Conduct a hypothesis test to determine i

Research Project

I have a team research project. We have completed the first part of the paper, but are stuck on where to go with the second half and need help with writing and research and statistical testing for it. I am posting both the first part assignment, and the 2nd part which we need help with. We need help with all parts of the 2nd ha

A Discussion On Significance Testing

A marketing analyst was studying the readability of two advertisements, each produced by a major company, and printed in the newspaper. A random sample of 100 marketing professors was selected. Fifty were randomly assigned to read the advertisement produced by Company A, and the other fifty were to read the advertisement produce

Hypothesis testing

The following hypothesis are given: Ho: p less or equal to 0 H1: p >0 A random sample of 12 observations indicated a correlation of .32 Can we conclude that the correlation in the population is greater than 0? Use the .05 significance level. Ho is rejected if t> 1.714 t= .32SQRT 32-5/SQRT 1-(.32)^=? I don't know

Applications of six-step hypothesis testing

Twelve students randomly selected from the entering class of college had the following SAT scores in math and English population mean=500, sigma=100 STUDENT ENGLISH MATH 1 500 545 2 551 662 3 493 561 4 519

6-step hypothesis testing

25 randomly selected tires from a tire company has the actual tread life: 40000 40100 38400 39170 36470 41360 37980 40060 38810 40370 39860 39280 41210 38660 38960 41780 39680 36240 38000 41120 39480 35160 42270 41320 39860 The company claims that this particular tire has a tread life of 40000 miles. Is this accurate or in

6-Step Hypothesis Testing with Light bulb Difference

A random sample of twelve 100 watt light bulbs made by Lite Up Your Life Inc had the following burn times: 1810, 1835, 1720, 1860, 2085, 1605, 1920, 1930, 1915, 1995, 1975, and 1975 hours. A random sample of fifteen 100 watt bulbs made by Lights R Us had the following burn times: 2065, 1855, 2135, 2129, 1795, 2245, 2085, 2135,

A 6-Step Hypothesis Test

A new procedure was tried on a number of patients. they were later asked whether they preferred the new procedure, the old procedure, or had no preference. Based upon the results, how do people feel? Use a 6 step hypothesis test prefer new prefer old no preference

Determining Preference

Six people have declared their intentions to run for a county commission seat in the next general election. A political poll is conducted three-quarters of the way into the campaign to determine if there are any clear preferences on the part of the voters. One thousand twenty randomly-selected voters were asked to indicate thei

Sampling to Derive Meaningful Statistics

--- 1. Given the following population data: 1,2,4,5,8,9,12, and the lists of all samples of size 2 and 5: Samples of n = 2 xbar Samples of n = 5 xbar 1,2 1.5 For population 1,2,4,5,8 4 1,4 2.5 s = ? 1,2,4,5,9 4.2 1,5 3 m = ? 1,2,4,5,12 4.8 1,8 4.5 1,2,4,8,9 4.8 1,9 5 1,2,4,8,12 5.4 1,12 6.5 1,2,4,

Hypothesis testing

The following are the GMAT scores and the GPA's of a random sample of 6 students in a graduate school. During a 'cram' weekend the students learned several GMAT applications. With a 0.05 los did the GPAs increase? BEFORE AFTER GMAT GPA GPA 610 3.60 3.70 470 3.25 3.30 590 3.50 3.45 520 3.

Hypothesis Testing Focused on Significance Levels

Surveys have been widely used by politicians around the world as a way of monitoring the opinions of the electorate. Six months ago, a survey was undertaken to determine the degree of support for national party leader. Of a sample of 1,100, 56% indicated that they would vote for this politician. This month, another survey of 800

Developing a hypothesis about a mean time

Studies from a local mall show the typical shopper spends 0.75 hrs shopping. The standard deviation is 0.10 hours. A sample of 45 shoppers revealed the mean time spent increased to .080 hrs. Develop a hypothesis to determine if the mean time spent is more than 0.75 hrs using the .05 significance level. Suppose the mean sh

This is a Statistics Problem

1. An experiment is designed to test the effectiveness of a specific type of gender selection process, using 15 couples trying to have baby girls. Here is the question: The empirical rule applies to bell-shaped (normal) distributions. Is the binomial probability distribution for this experiment approximately normal? Show w

Various Statistical Analyses

1. Suppose a sample of size 25 is selected from an underlying normal population, the population standard deviation is known to be 8, and the sample mean is 57. Carry out a hypothesis test at the 0.05 level of significance, where the null hypothesis H0 is  = 60 and the alternative hypothesis H1 is   60.