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Hypothesis Testing

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

Would like to find the p-value

The question asks the appeal of audiotapes for walking tours of eight major cities. The issue is if all the tapes are equally appealing, and what is distinctive about the p-value. SSTR = 7,102 SSE = 10,511 r = 8 ni = 20 MSTR = SSTR/(r-1) = 7102/7 = 1014.57 MSE = SSE/(n-r) = 10,511/(160-8) = 69.15 F(7,152) = 14.67

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

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 if t

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

Hypothesis testing of correlation coefficient

The following is a sample Quiz #1 Final 7 34 4 25 2.5 24 8 34 3 20 7.5 34 7.25 42 7 25 5 33 Conduct a hypothesis test to determine if there is a linear relationship (positive correlation) between the two scores or not. Remember to clearly state the null and alternate hypothesis and assume α = .05.

Hypothesis testing

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 ears o

Hypothesis testing

Before I moved to California, I sold my home in Nevada. My realtor told me that the average price of a 2500 square foot home in Nevada was $250,000. I really didn't trust him, so I took a sample of 100 people with 2500 square foot homes in Nevada and found that the average price of a 2500 square foot home was $260,000 with a

Null & Alternative Hypothesis & Five-Step Procedure

The null and alternate hypotheses are: Ho: µ1 = µ2 H1: µ1 >= µ2 A random sample of 15 observations from the first population revealed a sample mean of 350 and a sample standard deviation of 12. A random sample of 17 observations from the second population revealed a sample mean of 342 and a sample standard deviation of 15

Question about Test of mean

Given the following hypotheses: the true mean equals 100 (the null) and the true mean does not equal 100 (the alternate), a random sample of six resulted in the following values: 118, 105, 112, 119, 105, 111. Using = .05, can we conclude the true mean differs from 100? In the process of answering this question: a) state the deci


A TV add, aimed at men, claims that drinking a special weight loss medicine before every meal will result in the loss of at least 5 pounds after two weeks. A skeptical newspaper reporter decides to check if the plan works by having 10 randomly selected women follow the plan for the four week period. The weights for the indivi

Test Ho , mean , two tailed test

Test H0: μ1 - μ2 = 2, HA: μ1 - μ2 > 2, where u1 = 522, u2 = 516, s12 = 28, s22 = 24, n1 = 40, n2 = 30, at α = .01.

Test H0

Test H0: μ = 3.0 versus HA: μ > 3.0 when = 3.44, s = .57, and n = 13 at a significance level of .05. Assume population normality


5. The following data resulted from an experiment to study the effects of leaf removal on the ability of fruit of a certain type to mature: Treatment No of fruits matured No of fruits aborted Control 141 206 Two leaves removed 28


3. Auto Insurance Commissioner Auto insurance premiums in Massachusetts depend on the age of the driver and the driver's record but are not supposed to depend on gender. The state insurance commissioner wants to investigate whether there is any difference in the average premium that company A charges males and the average pre

Statistics Problem

The Atlanta Convention & Visitors Bureau just released a report on the percentage of available hotel rooms in Fulton County that were rented (occupied) in 2003. Looking over the report you note that room occupancy in March of 2003 was 77.6% (total rooms available is 14,800) and in December of 2003 it was 55.5% (of the 14,600 av