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Hypothesis Testing

A one sample test -topic 401K

Identify a research issue, problem, or opportunity that uses either interval or ratio level data (Recall that ratio level data are those data which have an absolute zero. This includes all forms of money, weight, time, or distance.) Some examples of ratio level data include a team member's 401K fund, a team member's stock portfo

Advantages of Accurate Interpretation of Statistics

The types kinds of statistical information collected in your professional setting. Provide examples to illustrate the information/data. b. The advantages of accurate interpretation of statistical information c. How this information is used to improve decision making in your organization

Blockbuster is testing a new policy of waiving all late fees on DVD rentals using a sample of 10 randomly chosen customers. (a) At alpha (a) = .10, does the data show that the mean number of monthly rentals has increased? (b) Is the decision close ? (c) Are you convinced?

Blockbuster is testing a new policy of waiving all late fees on DVD rentals using a sample of 10 randomly chosen customers. (a) At alpha= .10, does the data show that the mean number of monthly rentals has increased? (b) Is the decision close ? (c) Are you convinced? DVDRental Customer No Late fee Late

Two-Tailed Test and P-Value

The top food snacks consumed by adults aged 18-54 are gum, chocolate candy, fresh fruit, potato chips, breath mints/candy, Ice cream, nuts, cookies, bars, yogurt, and crackers. Out of a random sample of 25 men, 15 ranked fresh fruit in their top five snack choices. Out of a random sample of 32 women, 22 ranked fresh fruit in the


A sample of size 25 provides a sample variance of 400. The standard error, in this case equal to 4, is best described as the estimate of the standard deviation of means calculated from samples of size 25. Blossom's Flowers purchases roses for sale for Valentine's Day. The roses are purchased for $10 a dozen and are sold for

Degrees of Freedom

A political scientist obtained recordings of election-night acceptance speeches of seven newly elected representatives to the US Congress. She counted the number of minutes devoted to urban problems in these speeches. Four of the representatives were from rural districts and three were from urban districts. Listed below are the

How do you integrate ethics in your professional decision making process?

What is ethics? Ethics is basically concerned with the Moral obligations, responsibilities and social justice of the world. It invokes the idea of "how people should act". What is morals? Morals is your ability to know the difference between good and bad. Ethics is a construct made up of values. Ethical values include love, hone

Statistics Random Samples Z-Test

For the following independent random samples, use the z-test and the 0.01 level of significance in testing Ho:u1 = u2 versus H1:u1 = u2. x1 = 33.5 s1 = 6.4 n1 = 31 x2 = 27.6 s2 = 2.7 n2 = 30 2. The manager's assistant, who created a new brochure, randomly selects 400 current customers, then randoml

Statistics: P-value, Standard Deviation

Please show work! 1. A bottling company needs to produce bottles that will hold 8 ounces of liquid for a local brewery. Periodically, the company gets complaints that their bottles are not holding enough liquid. To test this claim, the bottling company randomly samples 64 bottles and finds the average amount of liquid held by t

Hypothesis Testing: Types of Samples

PROBLEM: Target wants to maintain adequate supplies of various brands of mouthwash to meet the on-going demands of its customers. Target wants to estimate the proportion of its customers who favor the country's leading brand of mouthwash, Scope. Are the data convincing evidence that something other than the historical 13% pre

Perform and independent samples t testt

You are interested in a new method of advertising. In order to test the new procedure they have tested it in eleven markets with the following sales in thousands of dollars: $124; $157; $98; $190; $103; $135; $149; $176; $200; $180; and $256. You also used eleven control markets, which had the following sales in thousands of d

Hypothesis test.

Research has demonstrated that involvement in religious activities seems to benefit health and well-being. Reyes-Ortiz, Ayele, Mulligan, Espino, Berges, and Markides (2006) found that church attendance was significantly related to fear of falling in a sample of Mexican-American aged 70 and over. The following frequency distri

Hypothesis Testing: Confidence Intervals

7. In a packing plant a machine packs cartons with jars. Supposedly a new machine will pack faster on the average than the machine currently used. To test that hypothesis the time it takes each machine to pack 10 cartons are recorded. The results in seconds are shown in the following table. New: 42,41,41.3,41.8,42.4,42.8,43.2,

Z test for population proportion

5. Of the 38 numbers on a roulette wheel, 18 are red, 18 are black and 2 are green. If the wheel is balanced, the probability of the wheel landing on red is 0.474. A gambler has been studying a roulette wheel. If the wheel is out of balance then he can improve his odds of winning. The gambler observed 200 spins of the wheel and

Statistics - Conclusion based on given data

The US energy administration publishes data on residential energy consumption and expenditures in residential consumption survey: consumption and expenditures. Suppose you want to decide whether last years mean annual mean expenditure for house holds using natural gas is different from that for house holds using only electricity

One Tail/Two Tail Rejection Regions

1. For each of the following statements, formulate appropriate null and alternative hypothese, indicate whether the appropriate test will be one-tail or two-tail, then sketch a diagram that shows the approximate location of the rejection region(s) for the test. a. The average college student spends no more than $300 per seme

Population Mean

A consumer agency has retained an independet testing firm to examine a television manufacturer's claim that its 25-inch console lmodel consumes just 110 watts of electricity. Based on a preliminary study, the population standard deviation has been estimated as 11.2 watts for these sets. In undertaking a larger study, and using

Statistics: Level of Significant Problems

The average length of a flight by regional airlines in the United States has been reported as 299 miles. If a simple random sample of 30 flights by regional airlines were to have x = 314.6 miles and s = 42.8 miles, would this tend to cast doubt on the reported average of 299 miles? Use a two-tail test and the 0.05 level of sig

Effects of TV viewing on reading scores

Dr. S wishes to measure the effect of TV viewing on reading scores in elementary school children. The data for the sample are shown here. Assume the population is normal. # hours TV/week (x): 4,5,8,12,20,16,20,22,22,25,30 Reading scores (y):805,810, 860,750,715,755,720,635,615,540,500 a.Construct a scatter plot using Mini

Applying statistics for smokers and nonsmokers

Dr. Z at the Clinic wishes to see whether the pulse rates of smokers are higher than the pulse rates of nonsmokers. Samples of 100 smokers and 100 nonsmokers are selected. The results are shown here. Can Dr. Z conclude, at alpha = 0.05, that the smokers have higher pulse rates than nonsmokers? Assume the samples come from a no

Creating Statistical analysis in SPSS and Interpreting Results

Introduction and Methods section: Impulse-Control disorder is a formal DSM IV disorder and is a core symptom that is found across an array of psycho-pathological conditions and consequently contributes to a large number of mental health problems in society. As cited in the Diagnostic and Statistical Manual of Mental Disorders

Planning Habits Survey/Null and alternative hypothesis

American Demographics reported the results of a survey on the planning habits of men and women. In response to the question. "What is your preferred method of planning and keeping track of meetings, appointments, and deadlines?, 56% of the men and 46% of the women answered "keep them in my head". A nationally represented sample

Hypothesis testing: chi square and z-stat. At the .05 level of significance, test the claim that at least half of all voters prefer the democratic candidate. Test the claim that the proportion with the lawn mowers is higher than 65%. Use a .01 significance level to test the claim that for men without college degrees in that town, incomes have a higher standard deviation when a random sample of 22 men resulted in incomes with a standard deviation of 925$

1. A poll of 1,068 Americans reveals that 48% of the voters surveyed prefer the Democratic candidate for president. At the .05 level of significance, test the claim that at least half of all voters prefer the democratic candidate. 2. A nationwide study of American homeowners revealed that 65% have one or more lawn mowers. A l

9 Introductory Statistic Problems

I need help with these nine stat. questions. They come in two labs. Lab 6 and 7 and you need to use the data in the excel. I need to use the top half of the lab to answer the questions for the bottom half of the lab. Thank You ------------------------------------------------------------------------ The goal of this l

At the banks: Single waiting line versus Multiple waiting lines

The listed values are waiting times (in minutes) of customers. Bank A (Single waiting line) 6.5, 6.6, 6.7, 6.8, 7.1, 7.3, 7.4, 7.7, 7.7, 7.7 Mean=7.15 Bank B (Multiple waiting lines) 4.2, 5.4, 5.8, 6.2, 6.7, 7.7, 7.7, 8.5, 9.3, 10.0 Mean=7.15 Questions: 1). Bank A customer will receive service within how many min

Simple analysis using Minitab

I need the analysis in Minitab and the same analysis in MS WORD, I do not have minitab on my comp here that is why I am having a problem. So give everything in word too. I will see the minitab file once i go to school. A data shows how many hours of south park do fisheries and wildlife student watch per week and then further

T-test: earnings per share for major companies reported 2002 earnings per share data for a sample of major companies (Feb. 12, 2003) Prior to 2002, financial analysts predicted the 2002 earnings per share for these same companies (Barron's Sep. 10, 2001) Use the following data to comment on differences between actual and estimated earnings per share. C