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Hypothesis Testing

Statistics of Ear Infections in Elementary School

Many elementary school students in a school district currently have ear infections. A random sample of children in two different schools found that 16 of 42 at one school and 21 of 36 at the other had this infection. At the .05 level of significance, is there sufficient evidence to conclude that a difference exists between the

Sample size and Hypothesis testing problems

Assignment 3 The Precision Scientific Instrument Company manufactures thermometers that are supposed to give readings of 0°C at the freezing point of water. Tests on a large sample of these thermometers reveal that at the freezing point of water, some give readings below 0°C (denoted by negative numbers) and some give readi

Calculation Test Statistic for T-Test

Citrus Rental is a popular car rental agency that has a history of having too few cars available, so that its available cars are overdriven. The mean monthly mileage over the years for Citrus cars has been about 1550 miles per month. Recently, though, Citrus purchased thousands of new cars, and the company claims that the ave

Measuring Employees' Job Satisfaction and Stress Level

You are the president of a medium size marketing research and management-consulting firm. ZYX Inc has hired you for a new management-consulting project. After interviewing the top management at ZYX, you have made the following notes: 1. ZYX Inc is a publicly owned electronics-manufacturing firm with over 1,500 employees. T

Two or More Sample Hypothesis Testing Paper

Describe the results of the nonparametric hypothesis test that includes the null hypothesis statement that there is no difference between the mean selling price of homes and the number of bedrooms each home has. The alternative hypothesis is that at least one of the mean selling prices of homes is different on the number of b

Evidence that Bank Supervisors Discriminated against Females

Forty-eight male bank supervisors were each given the same personal file and asked to judge whether the person should be promoted to a branch manager job that was described as "routine", or the file held and other applicants interviewed. The files were identical except that half of them showed that the file was that of a female

Hypothesis Testing, Significant Levels and p-Values

State and complete the 5 steps of Hypothesis Testing You may use the p - method or the traditional method. 1. A manufacturer makes steel rods that are supposed to have a mean length of 50 centimeters. A retailer suspects that the bars are being produced too short. A sample of 46 bars is taken and their mean length is

Gender and Potato Chip Preferences

Based on the provided data, you have been given the task of showing that there is a difference between gender and potato chip preferences. A colleague has obtained some sample data for you: Lays Jays Better Maid Private Label Male 16 6 5 10

Analyzing Categoric Data :Yule Q

1. In several presidential elections, researchers' have observed a "gender gap" in which men and women vote for candidates in different proportions. Test this hypothesis by calculating X2 and Yule's Q for these frequencies from the 1998 General Social Survey: Vote by Gender Did You Vote for Clinton or Dole? Men Women

P-Values and Critical Values

1. Based on the Nielsen ratings, the local CBS affiliate claims its 11:00 PM newscast reaches 41% of the viewing audience in the area. In a survey of 100 viewers, 36% indicated that they watch the late evening news on this local CBS station. a) What is the p-value? b) What is the critical value if = 0.01? 3.What is the


In a large class, the professor has each person toss a coin 200 times and calculate the proportion of his or her tosses that were heads. The students then report their results, and the professor plots a histogram of these several proportions. Use the 69-95-99.7 rule to provide the appropriate response. 1) About 68% should have

The Purposes of a Hypothesis Test

What is the purpose of a hypothesis test? What goes in the null hypothesis and what goes in the alternate hypothesis? Why is it inappropriate to put a sample statistic in the hypothesis? If you are testing the hypothesis H0: population proportion is .5 H1: population proportion is not .5, and you get .52 for the sample

Statistics definition and applications

Define and discuss the following statistical terms within the context of a business example. Each answer should be one paragraph in length. 1. Statistics and descriptive statistics 2. Population and Sample 3. Cardinal, Ordinal, and Scale Data 4. Random sample, random error, sampling error 5. Qualitative variables 6

Hypothesis Testing for Evidence

Suppose that in January 1999 it was reported that 58 percent of Americans rated the condition of the economy to be ``fairly good.'' In a Gannett News Service poll of 1003 Americans taken October 15--20, 1999, and reported in the October 31, 1999, issue of the Cincinnati Enquirer, 62 percent of those polled rated the condition of

Small sample hypothesis test for a population mean explained in this answer

The Smoky Bear Trucking Company claims that the average weight of a fully loaded moving van is 12,000 lbs. The highway patrol decides to check this claim. A random sample of 29 Smoky Bear moving vans shows that the average weight is 12,100 lbs with a standard deviation 800 lbs. Construct a hypothesis test to determine whether

Hypothesis Testing for a Soft-Drink Manufacturer

A soft-drink manufacturer claims that its 12-ounce cans do not contain, on average, more than 30 calories. A random sample of 16 cans of this soft drink, which were checked for calories, contained a mean of 31.8 calories with a standard deviation of 3 calories. Assume that the number of calories in 12-ounce soda cans is normal

Basic Large Sample Theory

Question: For i = 1,...,s and j = 1,...,ni , let Xij be independent with Xi,j having distribution Fi , where Fi is an arbitrary distribution with mean i and finite variances 2 that vary for each Fi......

Purpose of a hypothesis statement is given

1. What is the purpose of a Hypothesis Statement? 2. Null Hypothesis = H0 or H1 (circle one) Alternate Hypothesis = H0 or H1 (circle one) 3. What does ∑ mean and do? 4. Explain Alpha. 5. Are the Null and Alternate Hypothesis mutually exclusive? Y / N (circle one) 6. What are the generally accepted le

Scatterplot for o-ring failures

The space shuttle Challenger was in launch position the morning of January 28, 1986, with seven astronauts and passengers on board. Just prior to the launch, sheets of ice clung to the fuselage. Moments later, with national television coverage as it blasted into orbit, the shuttle disintegrated in a catastrophic explosion. The

One Sample Hypothesis Testing and Data Processing

Describe the results of a hypothesis test of one population mean or population proportion. Be sure to include the following in your answer: 1. Formulate both a numerical and verbal hypothesis statement regarding your research issue. 2. Perform the five-step hypothesis test on data pertaining to your selection. Step 1:

Statistics: Cash Withdrawal Analysis

Cash withdrawals (in multiples of $20) at an on-campus ATM for a random sample of 30 Fridays and 30 Mondays are shown below. At alpha = .01, is there a difference in the mean ATM withdrawal on Monday and Friday? (a) Make stacked dot plots of the data (a sketch is OK). (b) State the hypotheses. (c) State the decision rule a


Question 1 The SAT scores of entering freshmen at X University have a normal distribution with mean μ1 = 1200 and standard deviation σ1 = 90, while the SAT scores of entering freshmen at Y University have a normal distribution with mean μ2 = 1215 and standard deviation σ2 = 110. Independent random samples

Statistical Inference

1) Find the expected values of the following probabilities...... 2) In a population of test scores not known to be probability distributions.... 5) Using the sample limit theorem...... 8) The null hypothesis that --- equals 75 for a sample of 25 subjects.... 9) Test the null hypothesis that ---- equals 50 for a sampl

Two Sample Hypothesis Testing: Is unemployment related to imports/exports?

Need a comparison between unemployment and import export data for the four different countries (China, Chile, Canada, and United States). Using the dataset attached (AISE CIA Global Demographics) and reviewing the tabs in the excel document. Use the five step hypothesis testing procedure. I am writing a paper that states

Mixed Stats

For each of the following scores, use the one-tail five percent (5%) criteria and determine if the occurrence of the score would be considered relatively likely or unlikely? a. 18 b. 24 c. 25 7. For a two-tailed test or nondirectional hypothesis, the researcher is interested in results that occur in either tail of the nor

Statistics Project Using Microsoft Excel

Read the attached case study and complete the following: 1. Prepare a report exploring the data your team collected for the management of SJGR. This report should contain the results of the various data exploratory data analyses tools such as scatter charts, histograms, correlation coefficients, etc. and the interpretation of

One-sided Test

We analyze whether the true mean discharge of wastewater per hour from an industrial plant exceeds the company claims of 1000 gallons. For the decision in the one-sided test using a=0.05: A) If the plant is not exceeding the limit, but actually the M=1000, there is only 5% chance that we will conclude that they are exceeding

Hypothesis testing problems

1.A researcher collects infant mortality data from a random sample of villages in a certain country. It is claimed that the average death rate in this country is the same as that of a neighboring country, which is known to be 17 deaths per 1000 live births. To test this claim using a test of hypotheses, what should the null and

Hypothesis, P=values and rejection of null

Same sex marriages was legalized across Canada by the Civil Marriage Act enacted in 2005. Is this supported by the majority, or a minority, of the Canadian population. A poll conducted for the Globe and Mail newspapers in July 2005 of 1000 Canadians asked whether this bill should should stand or be repealed. The response were 55