OBHR 248 Quiz | Course Paper

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TABLE 9-8

One of the biggest issues facing e-retailers is the ability to turn browsers into buyers.

This is measured by the conversion rate, the percentage of browsers who buy something

in their visit to a site. The conversion rate for a company’s website was 10.1%. The

website at the company was redesigned in an attempt to increase its conversion rates. A

sample of 200 browsers at the redesigned site was selected. Suppose that 24 browsers

made a purchase. The company officials would like to know if there is evidence of an

increase in conversion rate at the 5% level of significance.

Referring to Table 9-8, state the null hypothesis for this study.

TABLE 16-4

The number of cases of merlot wine sold by a Paso Robles winery in an 8-year period

follows.

Referring to Table 16-4, exponential smoothing with a weight or smoothing constant of

0.4 will be used to smooth the wine sales. The value of E2, the smoothed value for 2006

is ________.

In testing for the differences between the means of two independent populations, you

assume that the 2 populations each follow a(n) ________ distribution.

TABLE 9-7

A major home improvement store conducted its biggest brand recognition campaign in

the company’s history. A series of new television advertisements featuring well-known

entertainers and sports figures were launched. A key metric for the success of television

advertisements is the proportion of viewers who “like the ads a lot”. A study of 1,189

adults who viewed the ads reported that 230 indicated that they “like the ads a lot.” The

percentage of a typical television advertisement receiving the “like the ads a lot” score

is believed to be 22%. Company officials wanted to know if there is evidence that the

series of television advertisements are less successful than the typical ad (i.e. if there is

evidence that the population proportion of “like the ads a lot” for the company’s ads is

less than 0.22) at a 0.01 level of significance.

Referring to Table 9-7, what will be the p-value if these data were used to perform a

two-tail test?

TABLE 2-12

The table below contains the opinions of a sample of 200 people broken down by

gender about the latest congressional plan to eliminate anti-trust exemptions for

professional baseball.

Referring to Table 2-12, of those neutral in the sample, ________ percent were males.

TABLE 16-5

The number of passengers arriving at San Francisco on the Amtrak cross-country

express on 6 successive Mondays were: 60, 72, 96, 84, 36, and 48.

Referring to Table 16-5, exponentially smooth the number of arrivals using a smoothing

constant of 0.1.

TABLE 18-9

The manufacturer of canned food constructed control charts and analyzed several

quality characteristics. One characteristic of interest is the weight of the filled cans. The

lower specification limit for weight is 2.95 pounds. The table below provides the range

and mean of the weights of five cans tested every fifteen minutes during a day’s

production.

Referring to Table 18-9, construct an R chart for the time required to register.

Referring to Table 14-14, the predicted mileage for a 300 horsepower,

6-cylinder car is ________.

TABLE 14-14

An automotive engineer would like to be able to predict automobile

mileages. She believes that the two most important characteristics

that affect mileage are horsepower and the number of cylinders (4 or

6) of a car. She believes that the appropriate model is

Y = 40 – 0.05X1 + 20X2 – 0.1X1X2

where X1 = horsepower

X2 = 1 if 4 cylinders, 0 if 6 cylinders

Y = mileage

TABLE 11-11

A student team in a business statistics course designed an experiment to investigate

whether the brand of bubblegum used affected the size of bubbles they could blow. To

reduce the person-to-person variability, the students decided to use a randomized block

design using themselves as blocks.

Four brands of bubblegum were tested. A student chewed two pieces of a brand of gum

and then blew a bubble, attempting to make it as big as possible. Another student

measured the diameter of the bubble at its biggest point. The following table gives the

diameters of the bubbles (in inches) for the 16 observations.

Referring to Table 11-11, what is the critical value of the randomized block F test for

the difference in the means at a level of significance of 0.05?

TABLE 12-15

Two new different models of compact SUVs have just arrived at the market. You are

interested in comparing the gas mileage performance of both models to see if they are

the same. A partial computer output for twelve compact SUVs of model 1 and thirteen

of model 2 is given below:

You are told that the gas mileage population distributions for both models are not

normally distributed.

Referring to Table 12-15, what is the value of the Z test statistic?