Question: To illustrate the effects of driving under
To illustrate the effects of driving under the influence (DUI) of alcohol, a police officer brought a DUI simulator to a local high school. Student reaction time in an emergency was measured with unimpaired vision and also while wearing a pair of special goggles to simulate the effects of alcohol on vision. For a random sample of nine teenagers, the time (in seconds) required to bring the vehicle to a stop from a speed of 60 miles per hour was recorded.
(a) Whether the student had unimpaired vision or wore goggles first was randomly selected. Why is this a good idea in designing the experiment?
(b) Use a 95% confidence interval to test if there is a difference in braking time with impaired vision and normal vision where the differences are computed as “impaired minus normal.” Note: A normal probability plot and boxplot of the data indicate that the differences are approximately normally distributed with no outliers.
> In the federal government’s Current Population Survey, the response rate for 20- to 29-year- olds is 85%; for individuals at least 70 years of age it is 99%. Why do you think this is?
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> The following data represent the measure of a variable before and after a treatment. Does the sample evidence suggest that the treatment is effective in decreasing the value of the response variable? Use the = 0.10 level of significance. Note: Assume t
> (a) Test whether /level of significance for the given sample data. (b) Construct a 95% confidence interval about /
> Explain why using the smaller of / degrees of freedom to determine the critical t instead of Formula (2) is conservative.
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> Student ID number
> Researchers wanted to determine if carpeted rooms contained more bacteria than uncarpeted rooms. To determine the amount of bacteria in a room, researchers pumped the air from the room over a Petri dish at the rate of 1 cubic foot per minute for eight ca
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> Test whether / level of significance for the given sample data.
> Many national polls are based on random-digit dialing (RDD). In this method, a computer randomly generates a phone number in the hopes of reaching an individual at his/her residence. In registration-based sampling (RBS), voter files are used to obtain a
> Test whether /level of significance for the given sample data.
> (a) Test whether /level of significance for the given sample data. (b) Construct a 95% confidence interval about /
> (a) Test whether /level of significance for the given sample data. (b) Construct a 90% confidence interval about /
> (a) Test whether /level of significance for the given sample data. (b) Construct a 95% confidence interval about /
> An experiment was conducted in which 16 ten-month-old babies were asked to watch a climber character attempt to ascend a hill. On two occasions, the baby witnesses the character fail to make the climb. On the third attempt, the baby witnesses either a he
> (a) Determine di = Xi - Yi for each pair of data. (b) Compute / (c) Test if /level of significance. (d) Construct a 99% confidence interval about the population mean difference /
> (a) Determine di = Xi - Yi for each pair of data. (b) Compute / (c) Test if / level of significance. (d) Construct a 95% confidence interval about the population mean difference /
> A researcher wants to show the mean from population 1 is less than the mean from population 2 in matched-pairs data. If the observations from sample 1 are Xi and the observations from sample 2 are / then the null hypothesis is / and the alternative hypot
> A researcher wants to show the mean from population 1 is less than the mean from population 2 in matched-pairs data. If the observations from sample 1 are Xi and the observations from sample 2 are /then the null hypothesis is /and the alternative hypothe
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> In an experiment conducted online at the University of Mississippi, study participants are asked to react to a stimulus. In one experiment, the participant must press a key on seeing a blue screen and reaction time (in seconds) to press the key is measur
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> A researcher wishes to determine the effects of alcohol on people’s reaction time to a stimulus. She randomly divides 100 people aged 21 or older into two groups. Group 1 is asked to drink 3 ounces of alcohol, while group 2 drinks a placebo. Both drinks
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> A sampling method is _____ when the individuals selected for one sample are used to determine the individuals in the second sample.
> A sampling method is ______ when the individuals selected for one sample do not dictate which individuals are selected to be in a second sample.
> Explain the difference between an independent and dependent sample
> Why do we use a pooled estimate of the population proportion when testing a hypothesis about two proportions? Why do we not use a pooled estimate of the population proportion when constructing a confidence interval for the difference of two proportions?
> On April 12, 1955, Dr. Jonas Salk released the results of clinical trials for his vaccine to prevent polio. In these clinical trials, 400,000 children were randomly divided in two groups. The subjects in group 1 (the experimental group) were given the va
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> OPDIVA is a drug developed by Brystol-Meyers Squib that is meant to treat metastatic melanoma, which is the worst form of skin cancer. Survival rates for patients with this cancer are 6 to 10 months. Historically, patients with metastatic melanoma were t
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> x1 = 804, n1 = 874, x2 = 892, n2 = 954, 95% confidence
> The General Social Survey asked, “About how often did you have sex in the past 12 months?” About 47% of respondents indicated they had sex at least once a week. In an internet survey for a marriage and family wellness center, respondents were asked, “How
> x1 = 28, n1 = 254, x2 = 36, n2 = 301, 95% confidence
> x1 = 109, n1 = 475, x2 = 78, n2 = 325, 99% confidence
> x1 = 368, n1 = 541, x2 = 421, n2 = 593, 90% confidence
> Test whether / /
> Test whether / /
> Test whether / /
> Test whether / /
> A psychologist wants to know whether subjects respond faster to a go/no go stimulus or a choice stimulus. With the go/no go stimulus, subjects must respond to a particular stimulus by pressing a button and disregard other stimuli. In the choice stimulus,
> An educator wants to determine whether a new curriculum significantly improves standardized test scores for third grade students. She randomly divides 80 third-graders into two groups. Group 1 is taught using the new curriculum, while group 2 is taught u
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> Surveys tend to suffer from low response rates. Based on past experience, a researcher determines that the typical response rate for an e-mail survey is 40%. She wishes to obtain a sample of 300 respondents, so she e-mails the survey to 1500 randomly sel
