The mean of racial tolerance among LAPD officers in a random sample of 30 officers is...

The mean of racial tolerance among LAPD officers in a random sample of 30 officers is 6.92 on a 9-point scale. The standard deviation is 1.5. Your hypothesis is that on average the mean tolerance is less than 5. Assume that mean tolerance in the universe under the null hypothesis is equal to 5.0. Which test do you use a t or z? What is the value of the test you chose?

Expert Solution

t test as SD for population is unknown

orchestra answered 2 years ago

A simple random sample of 30 items resulted in a sample mean of 30. The population...

A simple random sample of 30 items resulted in a sample mean of 30. The population standard deviation is 15. a. Compute the 95% confidence interval for the population mean. Round your answers to one decimal place. ( , ) b. Assume that the same sample mean was obtained from a sample of 120 items. Provide a 95% confidence interval for the population mean. Round your answers to two decimal places. ( , )

A random sample of 17 police officers in Oak Park has a mean annual income of...

A random sample of 17 police officers in Oak Park has a mean annual income of $35,800 and a standard deviation of $7,800. In Homewood, a random sample of 18 police officers has a mean annual income of $35,100 and a standard deviation of $7,375. Test the claim at α = 0.01 that the mean annual incomes in the two cities are not the same. Assume the population variances are equal. a. Write down the type of test you will...

A simple random sample of 30 items resulted in a sample mean of25. The population...

A simple random sample of 30 items resulted in a sample mean of 25. The population standard deviation is 7 . Round your answers to two decimal places a. What is the standard error of the mean, ? b. At 95% confidence, what is the margin of error?

A random sample of size 30 from an exponential distribution with mean 5 is simulated. Show...

A random sample of size 30 from an exponential distribution with mean 5 is simulated. Show the R-code to plot the empirical cdf for this sample along with the true cdf in the sample graph.

A random sample of size 30 from an exponential distribution with mean 5 is simulated. Describe...

A random sample of size 30 from an exponential distribution with mean 5 is simulated. Describe the process of plotting the empirical cdf for this sample along with the true cdf in the sample graph.

21. The mean BMI from a random sample of 30 men is 31.3 with standard deviation...

21. The mean BMI from a random sample of 30 men is 31.3 with standard deviation ? = 4.6. Suppose the distribution of BMI is approximately normal. Construct a 95% confidence interval of the population mean BMI. 22. (5 Points) A medical researcher wants to investigate the amount of time it takes for patients' headache pain to be relieved after taking a new prescription painkiller. She believes that the population is normally distributed with a standard deviation of σ =...

A random sample is selected from a normal population with a mean mu equals 30 space...

A random sample is selected from a normal population with a mean mu equals 30 space a n d space s tan d a r d space d e v i a t i o n space sigma equals 8. After a treatment is administered to the individuals in the sample, the sample mean is found to be M=33. (a) If the sample consists of n=16 scores is the sample mean sufficient to conclude that the treatment has a significant...

The mean annual salary of a sample of 400 Chief Investment Officers (CIOs) in Canada is...

The mean annual salary of a sample of 400 Chief Investment Officers (CIOs) in Canada is $215,620 with a standard deviation of $38,790. Calculate the margin of error and construct the 98% confidence interval for the true population mean salary for CIOs in Canada.

A random sample of 20 observations is used to estimate the population mean. The sample mean...

A random sample of 20 observations is used to estimate the population mean. The sample mean and the sample standard deviation are calculated as 162.5 and 22.60, respectively. Assume that the population is normally distributed. a. Construct the 99% confidence interval for the population mean. (Round intermediate calculations to at least 4 decimal places. Round "t" value to 3 decimal places and final answers to 2 decimal places.) b. Construct the 95% confidence interval for the population mean. (Round intermediate...

A random sample of 29 observations is used to estimate the population mean. The sample mean...

A random sample of 29 observations is used to estimate the population mean. The sample mean and the sample standard deviation are calculated as 130.2 and 29.60, respectively. Assume that the population is normally distributed Construct the 95% confidence interval for the population mean. Construct the 99% confidence interval for the population mean Use your answers to discuss the impact of the confidence level on the width of the interval. As the confidence level increases, the interval becomes wider. As...

Question