Question

In: Statistics and Probability

Even though the population standard deviation is unknown, an investigator uses z rather than the more...

Even though the population standard deviation is unknown, an investigator uses z rather than the more appropriate t to test a hypothesis at the .05 level of significance. (a) Is the true level of significance larger or smaller than .05? (b) Is the true critical value larger or smaller than that for the critical z?

Solutions

Expert Solution

a) if the true level of significance is smaller than 0.05 then we reject the null hypothesis and if true level of significance larger than 0.5 then we don't reject the null hypothesis.

b) if true critical value is larger than the critical z then we reject the null hypothesis and if it is less than critical z value then we accept or do not reject the null hypothesis.


Related Solutions

To estimate the mean of a population with unknown distribution shape and unknown standard deviation, we...
To estimate the mean of a population with unknown distribution shape and unknown standard deviation, we take a random sample of size 64. The sample mean is 22.3 and the sample standard deviation is 8.8. If we wish to compute a 92% confidence interval for the population mean, what will be the t multiplier? (Hint: Use either a Probability Distribution Graph or the Calculator from Minitab.)
Consider a normal population with an unknown population standard deviation. A random sample results in x−...
Consider a normal population with an unknown population standard deviation. A random sample results in x− = 47.50 and s2 = 27.04. a. Compute the 90% confidence interval for μ if x− and s2 were obtained from a sample of 15 observations. (Round intermediate calculations to at least 4 decimal places. Round "t" value to 3 decimal places and final answers to 2 decimal places.) b. Compute the 90% confidence interval for μ if x− and s2 were obtained from...
Consider a normal population with an unknown population standard deviation. A random sample results in x−...
Consider a normal population with an unknown population standard deviation. A random sample results in x− = 48.44 and s2 = 10.89. [You may find it useful to reference the t table.] a. Compute the 90% confidence interval for μ if x− and s2 were obtained from a sample of 7 observations. (Round intermediate calculations to at least 4 decimal places. Round "t" value to 3 decimal places and final answers to 2 decimal places.) b. Compute the 90% confidence...
Consider a normal population with an unknown population standard deviation. A random sample results in x−...
Consider a normal population with an unknown population standard deviation. A random sample results in x− = 52.15 and s2 = 21.16. [You may find it useful to reference the t table.] a. Compute the 95% confidence interval for μ if x− and s2 were obtained from a sample of 19 observations. (Round intermediate calculations to at least 4 decimal places. Round "t" value to 3 decimal places and final answers to 2 decimal places.) b. Compute the 95% confidence...
Consider the normal population with an unknown population standard deviation. A random sample results in xbar=...
Consider the normal population with an unknown population standard deviation. A random sample results in xbar= 64.54 and s^2=46.24 a) construct the 90% confidence interval for mu if xbar and s^2 were obtained from a sample of 23 observations( round intermediate calculations to at least 4 decimal places. Sample mean and sample standard deviation to 2 decimal places and t value to 3 decimals and final answer to 2 decimals) b) construct the 90% confidence interval for mu if xbar...
Confidence Intervals for Population Means When the Population Standard Deviation is Unknown. Use the table of...
Confidence Intervals for Population Means When the Population Standard Deviation is Unknown. Use the table of critical values of t to find the following: Construct a confidence interval for the population mean at the given confidence level. Remember to find your degrees of freedom. 4. n = 25, x = 56, s = 8, level of confidence is 95% 2 5. n = 36, x = 23.6 s = 4.2 level of confidence is 90% 6. Level of confidence is...
Even though there are cases of Down syndrome that are more severe than others, why do...
Even though there are cases of Down syndrome that are more severe than others, why do we treat all people born with Down syndrome as if they are the same as each other? Why is this question Important to you as a member of society? Detail the major developments in social science thinking that drive questions regarding the individual. Explain how finding the answer to the question might impact other around you. Detail the major developments in social science thinking...
Even though there are cases of Down syndrome that are more severe than others, why do...
Even though there are cases of Down syndrome that are more severe than others, why do we treat all people born with Down syndrome as if they are the same as each other? Why is this question important to me as a member of society? What are major developments in social science thinking that drive questions regarding studying the individual? Explain how finding the answer might impact others around you. Explain why studying human behavior and identity is a valuable...
3. Interval estimation of a population mean, population standard deviation unknown The Business Environment and Enterprise...
3. Interval estimation of a population mean, population standard deviation unknown The Business Environment and Enterprise Performance Survey (BEEPS), developed by the European Bank for Reconstruction and Development and the World Bank, is a survey of more than 4,000 firms in 22 transition countries. Conducted in 2000, BEEPS gathered information on the impediments to business growth in transition countries. As part of BEEPS, firms that import goods answered the question, “How many days does it take from the time your...
According to the 68-95-99.7 rule what percent of the population are more than 2 standard deviation...
According to the 68-95-99.7 rule what percent of the population are more than 2 standard deviation away from the mean?
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT