Drugstore.com was the first e-commerce company to offer Internet drugstore retailing. Drugstore.com 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
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
To determine confidence interval of mean and test if there is significant difference between means. See attached file for full problem description.
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
1. The mean weight for a certain type of fish is known to be 28.0 ounces with a standard deviation of 2.5 ounces . A game warden catches and weighs 30 fish from a certqin pond to check if they are larger than the mean stated above. If the mean of the sample is 30.9 ounces is this evidence of a significantly larger population of
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
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
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
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
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
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
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
1. For the data given, predict the sales when square footage is 2.6 and number of stores is 1950. 2. For the output interpret coefficient of determination and adjusted coefficient of determination, show how adjusted coefficient was calculated. 3. Identify p-values for the slopes. What do you conclude about significance of
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
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,
(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
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?
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
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
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
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
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.
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
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
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
As CEO of a large corporation, you are interested in the relationship of funds expended in research and corporate profit. The results are: p = .0013 and r = .91
1. In hypothesis testing, the level of significance is? 2. When would you use a t test and when would you use an f test ? 3. You are interested in the assumption that adult students earn better grades than traditional students. a. What is the independent variable ? b. What is the dependent variable ? c. What are the null an
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