A random sample of 100 students is selected from a certain school. They are given an IQ test which has a known population standard deviation of 11. The sample mean is found to be 112.
What type of inference procedure is appropriate here? Why?
The sample size is greater than 30 and we know the population standard deviation. Hence,
The appropriate inference procedure will be z test for single sample mean.
A random sample of 100 students is selected from a certain school. They are given an...
A principal at a specific school thinks that his students are above average intelligence. He collects a random sample of IQ scores from 25 students from his school. His sample has a mean of 112. The mean population IQ is 100 with a standard deviation of 15. Does he have enough evidence to support his claim?
A random sample of 61 fifth grade students was selected and given the Stanford-Binet IQ test. The mean score for the sample was 97, with an estimated standard error of the mean of 2.43. Estimate whether the sample mean could be representative of a population whose mean is 100. help please. step by step so that i could understand the process. HD backlit display 5. A random sample of 61 fifth grade students was selected and given the Stanford-Binet IQ...
The average starting salary of a random sample of 100 high school students was found to be $31,840. The population standard deviation for all such individuals is known to be $9,840. (12) Ten years ago, the average starting salary was $25,000. Does the sample data support the claim that the starting salary for this group has increased? Use alpha = 0.05. (6) Describe in general Type I and Type II errors and the Power of the test. (6) Describe in...
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Suppose you wish to determine if the mean IQ of students on a certain campus is different from the mean IQ in the general population, 100. To conduct this study, you obtain a simple random sample of 80 students on this campus, administer an IQ test, and record the results. The mean IQ of the sample of 80 students is found to be 108.5 with a standard deviation of 12.9. Complete parts (a) through (c) below. Determine the critical value(s)...
A random sample of 50 students is selected and it is found that the mean of daily internet usage is 70.8 minutes with standard deviation of 13.8 minutes. A hypothesis test was performed to determine whether the true mean usage, µ equal to 72.0 minutes or not. What is the p-value of the test?
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