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A salesman for a new manufacturer of cellular phones claims not only that they cost the retailer less but also that the percentage of defective cellular phones found among his products, ( p1 ), will be no higher than the percentage of defectives found in a competitor's line, ( p2 ).  To test this statement, the retailer took a random sample of 130 of the salesman's cellular phones and 110 of the competitor's cellular phones.  The retailer found that 10 of the salesman's cellular phones and 5 of the competitor's cellular phones were defective.  Does the retailer have enough evidence to reject the salesman's claim?  Use a significance level of α=0.05 for the test. Step 5 of 6 :  Determine the decision rule for rejecting the null hypothesis H0 . Round the numerical portion of your answer to three decimal places.

A company is considering an organizational change which entails adopting the use of self-managed work teams which they hope will lead to higher levels of employee satisfaction.  In order to assess the attitudes of employees of the company towards this change a sample of 250 employees was selected and asked whether they favor the institution of self-managed teams.  Three responses were allowed: favor, neutral or oppose.  The observed frequency of the results of the survey are shown below:         Opinion   Type of Job Favor Neutral Oppose Total Hourly Worker 25 40 35 100 Supervision 45 35 20 100 Manager 20 15 15 50 Total 90 90 70 250         Use this data to test the hypothesis that opinion and type of job are independent at the .025 level.

The manager of a men’s clothing catalog measured the market’s response to a $6 decrease in the usual price of his company’s oxford shirts by conducting a sales experiment.  An A-B split was used to divide the company’s 120,000-customer mailing list into two groups.  Customers in the control group were sent catalogs listing oxford shirts at their usual price of $40.  Customers in the test group were sent catalogs listing the price of oxford shirts at $32.80.  During the period of the test, customers in the control group purchased 700 oxford shirts, and customers in the test group purchased 889 oxford shirts. What is the independent variable in this sales experiment?  What is the dependent variable in this sales experiment? What is the percent change in price in this experiment?   What is price elasticity indicated by the results of this experiment.

William's Department Store is trying to determine whether there is a difference in mobile electronics sales for four different in-store locations. The company randomly chooses 20 same-sized stores that have similar storewide net sales. They randomly assign five stores to use the current mobile electronics aisle (In-aisle), five stores to use the special front location (front), five stores to use the kiosk location (kiosk), and five stores to use the expert counter (expert). The results are below. At the .05 level of significance, can William's Department Store conclude there is a difference among the mean sales among the four in-store locations? State H0 and H1 Should you reject or not reject H0

7. A television station wishes to study the relationship between viewership of its 11 p.m. news program and viewer age (18 years or less, 19 to 35, 36 to 54, 55 or older). A sample of 250 television viewers in each age group is randomly selected, and the number who watch the station’s 11 p.m. news is found for each sample. The results are given in the table below.

A salesman for a new manufacturer of cellular phones claims not only that they cost the retailer less but also that the percentage of defective cellular phones found among his products, ( p1 ), will be no higher than the percentage of defectives found in a competitor's line, ( p2 ).  To test this statement, the retailer took a random sample of 185 of the salesman's cellular phones and 150 of the competitor's cellular phones.  The retailer found that 22 of the salesman's cellular phones and 11 of the competitor's cellular phones were defective.  Does the retailer have enough evidence to reject the salesman's claim?  Use a significance level of α=0.05 for the test. Step 1 of 6 :  State the null and alternative hypotheses for the test.

If SLR 1-3 hold, but SLR 4 is violated, then...     OLS estimators are unbiased and inconsistent     OLS test statistics suffer from heteroskedasticity     OLS estimators are biased and consistent     OLS estimators are biased and inconsistent

A researcher is interested to search students’ willingness in participating in sport. Students are at undergraduate level and form different specialization studying in particular college. The researcher wants to interview students from all specializations in order to find whether there is a link between specialization and participation in sport. He arranges the by undergraduate specialization, next, he selects students randomly within each specialization. What is the name of sampling method?

Is it true or false that endogenous sample selection will not cause bias in the OLS estimator.

Previous answer was poorly formated

An automotive manufacturer wants to know the proportion of new car buyers who prefer foreign cars over domestic. Step 1 of 2 :  Suppose a sample of 1313 new car buyers is drawn. Of those sampled, 341 preferred foreign over domestic cars. Using the data, estimate the proportion of new car buyers who prefer foreign cars. Enter your answer as a fraction or a decimal number rounded to three decimal places.

Vida Dampo is the purchasing clerk for Adanfopa Company. Adanfopa sells car filters. One of the most popular filters is the BMW, which has an annual demand of 4,000 units. The cost of each filter is $90, and the inventory carrying cost is estimated to be 10% of the cost of each filter. Vida has made a study of the costs involved in placing an order for any of the filters that Adanfopa Company stocks, and she has concluded that the average ordering cost is $25 per order. Furthermore, it takes about two weeks for an order to arrive from the supplier, and during this time the demand per week for Adanfopa Company is approximately 80.i. What is the EOQ?ii. What is the ROP? iii. What is the average inventory? What is the annual holding cost? iv. How many orders per year would be placed? v. What is the annual ordering cost? note please answer all the questions.

Why can we not use first differences when we have independent cross sections in two years (as opposed to panel data)?

Suppose employers care about overall productivity Z, which is made up of two components, X and Y, such that Z=X+Y (and employers know this productivity function). Suppose there are two groups (male and female) whose average Zs are the same (i.e. Z_M =Z_F), but X_M < X_F and Y_M > Y_F (and again, employers know these population averages). Researchers decide to run a resume-based audit study where they randomize names based on gender (using typically male or female names) but hold constant Y. They provide no information on X. Which of the following would suggest taste-based discrimination? ● The call-back rate is the same for both sexes. ● The call-back rate is higher for men than for women ● We can't use differences in call-back rates to find suggestive evidence of taste-based discrimination because there's too many other factors that are different across the resumes. ● The call-back rate is higher for women than for men

A publisher reports that 50%50% of their readers own a particular make of car. A marketing executive wants to test the claim that the percentage is actually different from the reported percentage. A random sample of 240240 found that 45%45% of the readers owned a particular make of car. Determine the P-value of the test statistic. Round your answer to four decimal places.

A manufacturer of cat food was planning to survey households in the US to determine purchasing habits of cat owners. Among the questions to be included are those that relate to Where cat fat is primarily purchased. Whether dry or moist cat food is purchased. The number of cats living in the household. Whether the cat is pedigreed. Describe the population. For each of the four items listed, indicate whether the variable is categorical or numerical.

We are interested in analysing the effect of the lockout laws introduced in some areas of the Sydney CBD and nearby surrounds on the number of alcohol-related violent incidents.  Suppose we have two samples of data on the number of violent incidents in a number of local areas of the Sydney CBD and nearby surrounds. Pubs, hotels and clubs located in a subset of these areas became subject to the lockout laws when they were introduced in 2014. The first sample is from 2010 before the introduction of the lockout laws, and the second is from 2015 after the introduction of the law. The hypothesis we wish to test is that the introduction of the lockout laws reduces violent incidents in the areas in which the lockout laws were put in place.  We use a difference-in-difference model on the pooled data from 2010 and 2015. We find the following results: viol_inc hat = 33.21 (5.29) + 12.43lockout (7.01) – 4.19Yr2015 (2.98) – 3.32 (lockout x Yr2015) (1.85) N = 181, R^2 = 0.128 Where: viol_incis the…

Country Financial, a financial services company, uses surveys of adults age 18 and older to determine if personal financial fitness is changing over time (USA Today, April 4, 2012). In February 2012, a sample of 1000 adults showed 410 indicating that their financial security was more than fair. In February 2010, a sample of 900 adults showed 315 indicating that their financial security was more than fair. State the hypotheses that can be used to test for a significant difference between the population proportions for the two years. What is the sample proportion indicating that their financial security was more than fair in 2012? In 2010? Conduct the hypothesis test and compute the p-value. At a .05 level of significance, what is your conclusion? What is the 95% confidence interval estimate of the difference between the two population proportions?

You have been hired as a consultant by building contractor, who have been sued by the owners' representatives of a large condominium project for shoddy construction work. In order to assess the damages for the various units, the owners' association sent out a letter to owners and asked if people were willing to make their units available for destructive testing. Destructive testing was conducted in some of these units as a result of the responses. Based on the tests, the owners' association inferred the damage over the entire condo complex. Do you think that the inference is valid in this case?   a).  No, the inference is not valid. It is an example of sample selection bias because owners whose units were relatively more damaged were more likely to make theor units available for destructive testing.   b).  No, the inference is not valid because not all units were tested.   c).  Yes, the inference is valid. The study will correctly determine the incidence of damages in the concominium…

In 2009 a survey found these airline preferences for people in Southeast Asia when choosing to fly to China: 40%, Thai Airlines; 41%, Singapore Airlines; and 19%, Cathay Pacific. In 2011 this survey was repeated, and from a sample of 1,000 responders, 365 chose Thai, 540 chose Singapore, and 95 selected Cathay Pacific. Can you conclude that the consumers still have the same purchase patterns?

Please confirm if selected question is correct

A company that has a 15% market share launches a marketing campaign. At the end of the campaign period, the company conducts a survey in order to assess whether its market share has increased. From a survey issued to 500 customers after the campaign, the company found that 90 of them were committed to their products.  a.  Write the null and alternative hypotheses. b.  What is the value of the test statistic? c.  What is the associated P-value? d.  State your conclusion using α = 0.05.

PLS ANSWER Q5 and Q6

18. Car and Taxi Ages When the author visited Dublin, Ireland (home of Guinness Breweryemployee William Gosset, who first developed the t distribution), he recorded the ages of randomlyselected passenger cars and randomly selected taxis. The ages can be found from thelicense plates. (There is no end to the fun of traveling with the author.) The ages (in years) arelisted below. We might expect that taxis would be newer, so test the claim that the mean age ofcars is greater than the mean age of taxis.

In your own words, discuss the relationship between a t-test and a confidence interval.

Previous answer was wrong

UBC coaching center has two branches in Dhaka: one in Dhanmondi (Branch A) and another one in Mohammadpur (Branch B). To understand their students' performance, the coaching center conducts the same test in both branches. A sample of 8 students have been selected from branches A and B respectively, and the following table shows data on their performance. Use appropriate non-parametric methods on the data to find out whether there is a statistically significant correlation between the ranks of the students’ performance of the two branches.?

Is it possible for an econometric study to have internal validity but notexternal validity?

10.61 The per-store daily customer count (i.e., the mean number of customers in a store in one day) for a nationwide convenience store chain that operates nearly 10,000 stores has been steady, at 900, for some time. To increase the customer count, the chain is considering cutting prices for coffee beverages. The question to be determined is how much to cut prices to increase the daily customer count without reducing the gross margin on coffee sales too much. You decide to carry out an experiment in a sample of 24 stores where customer counts have been running almost exactly at the national average of 900. In 6 of the stores, the price of a small coffee will now be $0.59, in 6 stores the price of a small coffee will now be $0.69, in 6 stores, the price of a small coffee will now be $0.79, and in 6 stores, the price of a small coffee will now be $0.89. After four weeks of selling the coffee at the new price, the daily customer count in the stores was recorded and stored in . At the 0.05…

The U.S. Census Bureau conducts annual surveys to obtain information on the percentage of the voting-age population that is registered to vote.  Suppose that 450 employed persons and 477 unemployed persons are independently and randomly selected, and that 291 of the employed persons and 242 of the unemployed persons have registered to vote.  Can we conclude that the percentage of employed workers ( p1 ), who have registered to vote, exceeds the percentage of unemployed workers ( p2 ), who have registered to vote?  Use a significance level of α=0.05 for the test. Step 2 of 6 :  Find the values of the two sample proportions, pˆ1 and pˆ2 . Round your answers to three decimal places.

The U.S. Census Bureau conducts annual surveys to obtain information on the percentage of the voting-age population that is registered to vote.  Suppose that 450 employed persons and 477 unemployed persons are independently and randomly selected, and that 291 of the employed persons and 242 of the unemployed persons have registered to vote.  Can we conclude that the percentage of employed workers ( p1 ), who have registered to vote, exceeds the percentage of unemployed workers ( p2 ), who have registered to vote?  Use a significance level of α=0.05 for the test. Step 1 of 6 :  State the null and alternative hypotheses for the test.

As the Country Director of a multi-national company in Ghana, you have decided to conduct a survey to determine the perception of Ghanaians about a new alcoholic beverage you have introduced into the market. Identify, justify your choice, and explain any three (3) sampling techniques that can be employed for such a survey. Discuss how you will use each technique to select sampling elements for the study. Clearly explain how you will collect the data.