Statistics question
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An experiment was conducted to see what percentage of rats would show empathy toward fellow rats in distress. Of the 300 total rats in the study, 230 showed empathy. Construct a 99% confidence interval estimate of the population proportion of rats that show empathy.
Is it a mean problem or proportion problem?
What is the population being considered here?
Will you use z distribution or t distribution?
What is critical value?
Sample statistic:
Go to http://www.lock5stat.com/StatKey > Bootstrap CI > CI for single proportion > “Edit data” >
Count = 230 and sample size = 300
Generate 1000 samples > check “Two Tails”
CI =
Interpretation:
Check whether the sample size is large enough.
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In a simple random sample of 1219 US adults, 354 said that their favorite sport to watch is football. Construct a 95% confidence interval for the proportion of adults in the United States whose favorite sport to watch is football.
Is it a mean problem or proportion problem?
What is the population being considered here?
Will you use z distribution or t distribution?
What is critical value?
Sample statistic:
Go to http://www.lock5stat.com/StatKey > Bootstrap CI > CI for single proportion > “Edit data” >
Count = 354 and sample size = 1219 > generate 1000 samples > check “Two Tails”
CI =
Interpretation:
Check whether the sample size is large enough.
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A Gallup poll conducted a random sample survey in 2005 asked 1006 Americans how many books did they read in the past year. Results of the survey indicated the mean to be 13.4 books, with a sample standard deviation of 16.6 books. Construct a 99% confidence interval and interpret it’s meaning.
Is it a mean problem or proportion problem?
What is the population being considered here?
Will you use z distribution or t distribution?
What is critical value?
Sample mean: , sample SD =
Margin of error =
CI =
Interpretation:
Check whether the sample size is large enough.
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A random sample of 45 high school students has a skewed left distribution. The sample mean average ACT exam score was 20.8 with a sample standard deviation of 9.868. Statcato output of CI is given to you. Interpret the CI.
Sample size = CL =
Sample mean = Sample SD =
Margin of error = CI =
Interpretation:
Check whether the sample size is large enough.
SAMPLE ASSIGNMENT
