A majority of people who receive surveys in the mail don't respond. Researchers were curious which type of reward would be most effective: send someone $10 after they mail a completed survey back, or send someone
$5 with a survey as an advanced "thank you that they can keep whether or not they participate.
05
The researchers chose a random sample of 1200 adults and randomly assigned each of them to one of three
groups: $10 after, $5 in advance, or no reward at all. They found that people in the $5 group were significantly
more likely to send the survey back than people in either of the other groups.
What conclusion can they draw from this study?
Choose 1
Co
Survey completion caused the difference in reward type.
The $5 in advance caused the difference in survey completion
Pro
Pre
Any person given $5 in advance will completed this survey.
Tel
Any amount of money given in advance would lead to a higher response rate than any amount of
money given after
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Overproduction of uric acid in the body can be an indication of cell breakdown. this may be an advance indication of illness such as gout, leukemia, or lymphoma.† over a period of months, an adult male patient has taken nine blood tests for uric acid. the mean concentration was x = 5.35 mg/dl. the distribution of uric acid in healthy adult males can be assumed to be normal, with σ = 1.87 mg/dl. (a) find a 95% confidence interval for the population mean concentration of uric acid in this patient's blood. what is the margin of error? (round your answers to two decimal places.) lower limit upper limit margin of error (b) what conditions are necessary for your calculations? (select all that apply.) σ is unknown n is large σ is known normal distribution of uric acid uniform distribution of uric acid (c) interpret your results in the context of this problem. there is not enough information to make an interpretation. the probability that this interval contains the true average uric acid level for this patient is 0.05. the probability that this interval contains the true average uric acid level for this patient is 0.95. there is a 95% chance that the confidence interval is one of the intervals containing the population average uric acid level for this patient. there is a 5% chance that the confidence interval is one of the intervals containing the population average uric acid level for this patient. (d) find the sample size necessary for a 95% confidence level with maximal margin of error e = 1.10 for the mean concentration of uric acid in this patient's blood. (round your answer up to the nearest whole number.) blood tests