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Hypothesis Testing

Compare the Concepts of Estimation and Hypothesis

11. From the population of unknown mean μ and a standard deviation σ = 5.0, a sample of n= 100 is selected and the sample mean 40.6 is found. Compare the concepts of estimation and hypothesis testing by answering the following: a. Determine the 95% confidence interval for μ. b. Complete the hypothesis test

Business Stats

(See attached file for full problem description) --- 15 pts. 4. We want to develop a model to predict the selling price of a home based upon the assessed value. A sample of 30 recently sold single-family houses is selected. The results are as follows: Observation Assessed Value (000) Selling Price(000) 1 78.17 94.10 2 8

Testing Categorical Probabilities: One-Way Tables

Inc. Technology reported the results of an Equifax/Harris Consumer Privacy Survey in which 328 Internet users indicated their level of agreement with the following statement:"The government needs to be able to scan internet messages and user communications to prevent fraud and other crimes." The number of users in each response

Inferences based on 2 samples

Excess postexercise oxygen consumption (EPOC) describes the energy expended during the body's recovery period immediately following aerobic exercise. A journal published a study designed to investigate the effect of fitness level on the magnitude and duration of EPOC. Ten healthy young adult males volunteered for the study. Five

Inferences based on Single Samples

A consumer protection group is concerned that a ketchup manufacturer is filling its 20-ounce family-size containers with less than 20 ounces of ketchup. The group purchases 10 family-size bottles of this ketchup, weighs the contents of each, and finds that the mean weight is equal to 19.86 ounces, and the standard deviation is e

Inferences Based on Single Sample

An article in the Annals of the Association of American Geographers (June 1992) revealed that only 133 of 337 randomly selected residences in Los Angeles County were protected by earthquake insurance. -What are the appropriate null and alternative hypotheses to test the research hypothesis that less than 40% of the residents

Sampling and X-bar Distribution

A Company produces candy on a production line. When operating properly, the production process will produce an average of u=140 pounds of candy per hour with a standard deviation of o=20 pounds of candy per hour. It is also known that the distribution is skewed left. In order to monitor the assembly process, 100 hours are ran

Null hypothesis

Here are some things I need help with: ? ALWAYS write out the NULL & HYPO (they come as a set) even if the assignment does not ask you to do so ? Even though you write hypotheses using mathematical notations, it is important to also get in the habit of writing them in words too... things do get more complicated ? Alwa

Car Dealership, Level of Significance, Digital Camera

4. Car dealership chain owner wants to increase the car sales of his chain. He wants to determine which factors influence the sales performance. Owner thinks that the following factors have a significant impact on sales performance: X1 = number of years of experience as a car sales person X2 = age Sales performance is me

Statistical Hypothesis Testing: Crusty The Clown' Cereal

1. The sales of Crusty The Clown cereal since 2000 are: Year Code Sales ($ millions) 2000 1 5 2001 2 7 2002 3 6 2003 4 10 2004 5 12 What is the sales forecast for 2005? 2. The owner of a car dealership wants to determine whether there is a relation between the income level and the ty

Hypothesis testing

I am a manufacturer of refrigerators. Historically ( the last year of manufacturing) I averaged 200 units a week with a 10 unit standard deviation. Recently we upgraded some of the line to improve production. I took a random sample over 30 random weeks and came up with a sample average of 205 units Did I make improvements

Test of hypothesis

3-10. A researcher interested in the senses of taste and smell has carried out extensive studies in which university students are given each of 20 different foods (apricot, chocolate, cherry coffee, garlic, and so on). She administers each food by dropping a liquid on the tongue. Over the entire student population at her univers

Dependent Variables and Independent Variables

The owner of Maumee Ford-Mercury wants to study the relationship between the age of a car and its selling price. Listed below is a random sample of 12 used cars sold at the dealership during the last year. Car Age (years) Selling Price ($0.00) 1 9 8.1

Hypothesis Test on population proprotion

Tourism is one consideration for CoffeeTime's future, A survey of 1,233 visitors to mumbai last year revealed that 110 visited a small cafe during their visit. Laura claims that 10% of tourists will include a visit to a cafe.

Statistics Review - Significance Level, P-Value

1. A financial analyst wants to compare the turnover rates, in percent, for shares of oil-related stocks versus other stocks, such as GE and IBM. She selected 32 oil-related stocks and 49 other stocks. The mean turnover rate of oil-related stocks is 31.4 percent and the standard deviation 5.1 percent. For the other stocks, the m

Statistics Review Problem Set

1. The following is a hypothetical set of anxiety scale scores from a population of students being seen at a college counseling center: 5 16 47 6 18 50 9 25 50 10 46 50 12 47 78 What are the Z and the T scores of the person who scored 6? 18? Of the two people who scored 47? Of the person who scored 78? Why is it not a

Statistic Mean and Sampling

Clark Heter is an industrial engineer at Lyons Products. He would like to determine whether there are more units produced on the afternoon shift than on the day shift. A sample of 54 day-shift workers showed that the mean number of units produced was 345, with a standard deviation of 21. A sample of 60 afternoon-shift workers sh

Hypothesis Testing - Highschool Smoking

2) In 1999 the Center of Disease Control estimated that about 34.8% of high-school students smoked cigarettes. They established a national health goal of reducing that figure to 16% by the year 2010. To that end, they hoped to achieve a reduction to 30% by the end of 2001. Early in 2002 they released a research study in which on

Statistics Data Help

I am doing a project where I am comparing the accuracy and reproducibility of 3 different force gauges with varied angles and applied pressures. All of the gauges have a 50 lb. capacity. They will all be tested with 0-30 lbs in 5 lb increments of applied load/pressure. They will also be tested at 0 degrees (true perpendicular)

Hypothesis test

For a number of years... In the first year after the change, there were 56- survivors in a class of 800. Is this increase explainable as simply sampling variability? Test at a=0.01. Please see attached.

Hypothesis test

Seven skulls... Use these statistics in a test of the hypothesis that these skulls belong to a race previously found nearby in which the average width if known to be 146mm. Assume a nearly normal population. Perform the test a=0.1. Please see attached.

Statistics - Baseball Team Scores

Perform each of the steps below using Excel. Use the collected data from the chart (MLB Statistics) as a sample of the population (Any one statistic you choose). Describe the population that the data represents. Interpret each of your results with a conclusion and decision. Use any statistic on the MLB chart to answer the questi

Hypothesis Testing, Mean and Standard Deviation

26. To obtain information on the corrosion-resistance properties of a certain type of steel conduit, 45 specimens are buried in soil for a 2-year period. The maximum penetration (in mils) for each specimen is then measured, yielding a sample average penetration of x-bar= 52.7 and a sample standard deviation of s = 4.8. The condu

Statistics Questions

Does correlation equal causation? Why or why not? What is the relationship between correlation and association? What is association? When would you use regression correlation at your place of employment, in your education, or in politics? How do you identify outliers in your data? What are the differences between

Using AIU's large data base of survey responses from unit 2 Individual project (keep in mind this data base is your sample), you will begin testing hypothesis. Complete all of the following:

Using AIU's large data base of survey responses from unit 2 Individual project (keep in mind this data base is your sample), you will begin testing hypothesis. Complete all of the following: 1. Test a hypothesis to see whether the average overall job satisfaction (in the population of all workers in the USA) is equal to 4.5=.

5 Step Hypothesis Testing Procedure

Ms Lisa is the budget director for the New Process Company. She would like to compare the daily travel expenses for the sales staff and the audit staff. She collected the following sample info: Sales ($) 131 135 146 165 136 142 Audit ($) 130 102 129 143 149 120 139 At the .10 confidence level, canshe conclude that the mea