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Hypothesis Testing

Help solving these Probability Problems

1) Ms. Maria Wilson is considering running for mayor of the town of Bear Ghulch, Montana. Before completing the petitions, she decides to conduct a survey of voters in Bear Gulch. A sample of 400 voters reveas that 300 would support her in the November election. a) estimate the value of the population proportion. b) comput

Hypothesis Testing with Proportions

#10 The chief of security for the Mall of the Dakotas was directed to study the problem of missing goods. He selected a sample of 100 boxes that had been tampered with and ascertained that for 60 of the boxes, the missing pants, shoes, and so on were attributed to shoplifting. For 30 other boxes employees had stolen the goods

Two-sample Dependent or Matched pairs T-test

Because of uncertainty in real estate markets, many homeowners are considering remodeling and constructing additions rather than selling. The most expensive room in the house to remodel is the kitchen, with an average cost of $23,400. In terms of resale value, is remodeling the kitchen worth the cost? The following cost and r

One-Sample T-Test Command

The national average for the price of a gallon of unleaded regular gas is $1.16. I believe the price is higher in my area of the country. I want to test my claim by randomly selecting gas prices for 25 stations in my area. The following prices are: $1.27 $1.29 $1.16 $1.20 $1.37 1.20 1.23 1.19 1.20 1.24

5 Steps in hypothesis Testing

Need help working my way through the rest of the 5 steps with the information given. The null hypothesis is the average miles per gallon of fuel used in the Toyota Highlander hybrid vehicle, ?h is higher to equal to than that of a Toyota Hylander standard eight cyclinder, ?8. The alternative hypothesis is the average miles per

Population and Sample Standard Deviation

1.)If the population standard deviation ( s) is known then we use it in calculating the z-statistic as follows. z= [Xbar - m ] / [ s/ sqrt(n) ] On the other hand if population standard deviation is unknown, we substitute the sample standard deviation (s) in place of population standard deviation in calculating the z-statist

Hours spent at desktop computers

The manager of a computer software company wishes to study the number of hours senior executives spend at their desktop computers by type of industry. The manager selected a sample of five executives from each of three industries. At the .05 significance level, can she conclude there is a difference in the mean number of hours s

T-test statistics questions

1. 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 level of significance did the GPAs increase? BEFORE AFTER

Hypothesis testing

A national survey of restaurant employees found that 75% said work stress had a negative impact on their personal lives. A sample of 100 employees from a popular restaurant chain finds that 68 answer "Yes" when asked, "Does work stress have a negative impact on you personal life?" Is there a eason to believe the restaurant chain

Hypothesis testing, scatter diagrams, test statistics

(See attached file for full problem description) --- 1. The manager of the BiLo Supermarket in Mt. Pleasant, Rhode Island, sampled the following information on the number of times a customer visits the store during a month. The responses of 51 customers were. If EXCEL is used, please import the information into this test d

Sample Size Statistic

HI, I am having difficulty understanding statistics. I had just completed a paper in which I made a statistical comparison using gas prices in 1975 and 2006. The gas prices were in today's dollars. I need to do a small sample size statistic with the same info and I'm lost. Could you walk me through this with the 5 step hypoth

Statistics was the first e-commerce company to offer Internet drugstore retailing. customers were provided the opportunity to buy health, beauty, personal care, wellness, and pharmaceutical replenishment products over the Internet. At the end of 10 months of operation, the company reported that 44% of orders wer

Statistics- Test of hypothesis: Assume that for a sample of 40 days during the first half of 2003, the daily audience was 612,000 viewers with a sample standard deviation of 65,000 viewers. a. Develop the hypotheses if CNN management would like information on any change in the CNN viewing audience. b. Determine the p-value.

AOL Time Warner Inc.'s CNN has been the longtime ratings leader of cable television news. Nielsen Media Research indicated that the mean CNN viewing audience was 600,000 viewers per day during 2002 (The Wall Street Journal, March 10, 2003). Assume that for a sample of 40 days during the first half of 2003, the daily audience was

Test of hypothesis

Reis, Inc., a New York real estate research firm, tracks the cost of apartment rentals in the United States. In mid-2002, the nationwide mean apartment rental rate was $895 per month (The Wall Street Journal, July 8, 2002). Assume that, based on the historical quarterly surveys, a population standard deviation of s = $225 is rea

Testing Random Samples

A) An iron foundry asserts that the mean weight of the castings it produces is 20.0 kg. The weights of a sample of 10- castings are: 19.8 20.3 20.6 21.1 19.3 19.6 20.1 20.8 21.1 21.3 Assuming that the weight of a casting has an approximately normal distribution, test whether or not the assertion is correct. b) The poli

Population & Sample Size Questions

1.Why would you use a small sample to draw inference about a large population? Test of a single proportion: 2. What is the difference between a sample parameter (X-bar and s) and a proportion parameter (p)? Test of two populations, large sample size (z-statistics) 3. When would you use two population test with a larg

Golf cart assembly hypothesis testing with steps

What are the 5 hypothesis steps? 1. 2. 3. 4. 5. 2. The management of White industries is considering a new method of assembling its golf cart. The present method requires 42.3 minutes, on the average, to assemble a cart. The mean assembly time for a random sample of 24 carts, using the new method, was 40.6 minutes, an

Hypothesis Testing

I'm having difficulty understanding hypothesis testing. I need some assistance putting together a hypothesis test for comparing 1970s gasoline prices and 2006 gasoline prices. I need to find out if they are actually higher overall now as compared to 30 years ago. What formula should I use? And how should I put it into the five-s

Statistics: Tests of Between-Subject Effects

Please see the attached file. --- Question 12 Choose the statement that best applies to the following example and SPSS output. Dana wishes to assess whether vitamin C is effective in the treatment of colds. To evaluate her hypothesis she decides to conduct a 2-year experimental study. She obtains 30 volunteers from u

Calculatinga t-statistic for a grocery store comparison

The table below compares the prices of two online grocery stores. (see attached table) Using the table, which of the following is the correct calculation of the t statistic needed to test the null hypothesis that there is no difference in the average price of items at the two stores? A. -0.011 B. -0.541 C. -1.746

Critical Value for Rejecting Null Hypotheses

Assembly line workers are randomly assigned to two groups with 21 workers in each group. Each group receives a different training program and then their scores on an assembly task are compared. The "F" statistic for the variance in the two groups is 0.178. Using a 0.05 level of significance, what are the critical values for rej

Hypothesis testing for proportions: At alpha = .01, can we conclude that the proportion of democrats who favor "junk food" tax is more than 5% higher than proportion of republicans who favor the new tax?

Let p1 represent the population proportion of U.S. Senate and Congress (House of Representatives) democrats who are in favor of a new modest tax on "junk food". Let p2 represent the population proportion of U.S. Senate and Congress (House of Representative) republicans who are in favor of a new modest tax on "junk food". Out of

Hypothesis testing, independent variables, multiple regression models

1. _____ variation is the sum of explained variation plus the sum of unexplained variation. 2. The error term in the regression model describes the effects of all factors other than the independent variables on y (response variable). TRUE OR FALSE? 3. If we increase the number of independent variables in a multiple regre

Hypothesis testing for a grocery store and national safety council

Each part (a-d) of this problem gives the population standard deviation σ;, the statement of a claim about μ, the sample size n, the desired level of significance α. Formulate (i) the hypotheses, (ii) the test statistic Z, (iii) the rejection region. the answers to part (a) are provided. (a) σ = 2 claim: μ > 30,

This posting shows steps in formal hypothesis testing process.

(See attached file for full problem description) 1. What are the steps in formal hypothesis testing? Make at least two explanatory comments about each step. Step 1: Formulate the null and the alternative hypotheses. The null hypothesis is designated H0 while the alternative hypothesis is identified as H1. The null sh

Hypothesis testing

The following hypotheses are given: H0: π 0.70 H1: π >0.70 A sample of 100 observations revealed that p = 0.75. At the .05 significance level, can the null hypothesis be rejected? 1. State the decision rule. 2. Compute the value of the test statistic. 3. What is your decision regarding the null hypothesis?

Correlation Coefficient and Hypothesis testing

To play at East Texas State University has five scholarships available for the women's basketball team. The head coach provided the two assistant coaches with the names of 10 high school players with potential to play at East Texas State. Each assistant coach attended three games and then ranked the 10 players with respect to po

Hypothesis testing

The New York Times recently reported that 60% of college entrants into elite public and private colleges in the U.S. have parents that earn over $150,000/yr. In a sample of 1,000 new college freshmen you find that 57.75% of them have parents who earn over $150,000/yr. Conduct a hypothesis test to determine if the New York Time

Hypothesis testing

Electricity is commonly traded at the California-Oregon border (COB) and Palo Verde (PV) in Arizona. Assume you take a sample of 100 daily electricity market closing prices (in $/megawatthour) from both COB and PV. The following are the summary statistics resulting from your sample: COB PV Average Price $200 $300 Stan