an e-store that sells cell phone accessories report that 98% of its customers are satisfied with the speed of delivery. specify what type of bias is involved.

The Energy Star rating system is an energy efficiency program run by the U.S. Environmental Protection Agency (EPA)Energy Star certified appliances, such as televisions and refrigerators, are rated in regard to their average energy consumption per year. A certain brand of Energy Star certified refrigerator is stated to have a mean yearly electricity cost of $99. A consumer advocacy organization believes that this claim is wrong, that the energy consumption of this particular refrigerator is different than $99 per year. The group collected a random sample of 16 refrigerators of the model in question and had each lab-tested for electricity consumption. The yearly energy consumption of each is given below. 96.7697.898.67 95.52 97.8 95.896.9299.57 97.64 95.46 98.03 96.42 99.32 98.99 95.2197.12 Using alpha = 0.1 , test the hypothesis that the average yearly electricity consumption of the refrigerator in question is different than $99 per year. Assume that the distribution of all electricity…

Among college students, the proportion p who say they’re interested in their congressional district’s election results has traditionally been 65% . After a series of debates on campuses, a political scientist claims that the proportion of college students who say they’re interested in their district’s election results is more than 65% . A poll is commissioned, and 194 out of a random sample of 270 college students say they’re interested in their district’s election results. Is there enough evidence to support the political scientist's claim at the 0.05 level of significance? Perform a one-tailed test. Then complete the parts below. Carry your intermediate computations to three or more decimal places. (If necessary, consult a list of formulas.)   (a) State the null hypothesis H0 and the alternative hypothesis H1 . H0: H1: (b) Determine the type of test statistic to use.   ▼(Choose one)   (c) Find the value of the test statistic.…

In order to estimate the proportion of students at a small liberal arts college who watch reality TV for more than 4 hours per week, a random sample of students at the school is selected and each is interviewed about his or her reality TV viewing habits. The students conducting the survey are worried that people that watch reality TV might be embarrassed to admit it and that they may not respond to the survey with honest answers. What type of bias are the students conducting the survey worried about? Measurement or response bias They shouldn't worry--there is no obvious source of bias. Selection bias Nonresponse bias

Recent research commissioned by Vodafone suggests that older workers are the happiest employees (BBC News, July 21, 2008). The report documents that 70% of older workers in England feel fulfilled, compared with just 50% of younger workers. A demographer believes that an identical pattern does not exist in Asia. A survey of 120 older workers in Asia finds that 78 feel fulfilled. At a 5% level of significance, test if older workers in Asia feel less fulfilled than their British counterparts. In the box below, answer the following (a) What is the p-value for the test? (Round to three decimal places.) (b) At a 5% level of significance, do older workers in Asia feel less fulfilled than their British counterparts?

Levi-Strauss Co manufactures clothing. The quality control department measures weekly values of different suppliers for the percentage difference of waste between the layout on the computer and the actual waste when the clothing is made (called run-up). The data is in the table, and there are some negative values because sometimes the supplier is able to layout the pattern better than the computer. Do the data show that there is a difference between some of the suppliers? Test at the 1% level. Run-ups for Different Plants Making Levi Strauss Clothing Difference Plant Plant 1 11.9 Plant 1 3.9 -10.6 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 3 Plant 3 Plant 3 Plant 3 Plant 3 Plant 3 Plant 3…

A car wash is assessing the average wait time for its customers. The median wait time is 4 minutes. Does a customer who waits for 5 minutes represent an abnormal wait time? The customer who waits 5 minutes an abnormal case, because 50% of customers wait more than minutes.

GMU uses a robot food delivery service which now has been utilized in the City of Fairfax. One of the potential benefits of this service is to help the busiest students eat breakfast. Research has shown that about 80% of college students skip breakfast due to busy schedules and other reasons. Initial data were collected from a random sample of 595 Mason students who utilize the robot food delivery service and are presented in StatCrunch.    Show the full calculation of the sample proportion by including the number of students who skipped breakfast, the total number of students sampled, and the value of the sample proportion. Present this sample proportion as a decimal rounded to four decimal places. Frequency table results for Breakfast?Count = 595 Breakfast? Frequency Relative Frequency 0 142 0.23865546 1 453 0.76134454

A nationwide job recruiting firm wants to compare the annual incomes for childcare workers in Connecticut and California. Due to recent trends in the childcare industry, the firm suspects that the that the mean annual income of childcare workers in the state of Connecticut is greater than the mean annual income of childcare workers in California. To see if this is true, the firm selected a random sample of 10 childcare workers from Connecticut and an independent random sample of 10 childcare workers from California and asked them to report their mean annual income. The data obtained were as follows. 80°F Partly sunny Annual income in dollars Connecticut 42438, 52287, 46837, 49334, 52848, 52929, 57111, 51860, 44967, 52174 California 50998, 38334, 56804, 50919, 49446, 41141, 45717, 43963, 55156, 47295 LL D 144Hz Send data to calculator V The population standard deviations for the annual incomes of childcare workers in Connecticut and in California are estimated as 6300 and 6100,…

A community college professor is interested in determining the relationship between the number of posts students make on Schoology and their respective grades. He planned to correlate the results from a sample from all his classes, however, due to time constraints, he decided to sample only from students with high grades. As his statistical consultant, state whether or not you support his plans and why.