Question 10- Estimating and Testing Population Variance

.com/5eb1a317e2761/8286408?response-cache-control-private%2C%20max-age%3D21600&response-conte 6/6 QUESTION 10 (10 points) - Estimating and Testing Population Variance A simple random sample was drawn from a normal population with unknown variance : Observation 1 2 3 5 22.4 21.2 24.8 15.0 20.3 (a)[1] What information justifies a Chi-square sampling distribution of (n-1)s/o?? (b)[1] Use Excel to complete the lookup table below. (C)[3] Construct the 95% confidence interval for o?, then for o. Sketch the Cl foro. (d)[3] At the level of significance a = 0.10, test Ho: os 10 versus Hy o* > 10. (e)[2] Sketch and find the p-value of the test in part (d). Comment on the p-value. Hint: Use 5 decimals. Use Excel to find some lookups and refer to those for your answers: 0.0250 0.0250 0.9750 0.9750 0.9000 x 4.20736 4.73328 5.25920 5.25920 6.31104 5 4 4 CHISQ.INV(av,d) 0.83121 ? 12.83250 ? CHISQ.DISTIX df, 1) 0.62133 ? 0.73828 ? 0.82291 4 5 ? .com/5eb1a317e2761/8286408?response-cache-control-private%2C%20max-age%3D21600&response-conte 6/6 QUESTION 10 (10 points) - Estimating and Testing Population Variance A simple random sample was drawn from a normal population with unknown variance : Observation 1 2 3 5 22.4 21.2 24.8 15.0 20.3 (a)[1] What information justifies a Chi-square sampling distribution of (n-1)s/o?? (b)[1] Use Excel to complete the lookup table below. (C)[3] Construct the 95% confidence interval for o?, then for o. Sketch the Cl foro. (d)[3] At the level of significance a = 0.10, test Ho: os 10 versus Hy o* > 10. (e)[2] Sketch and find the p-value of the test in part (d). Comment on the p-value. Hint: Use 5 decimals. Use Excel to find some lookups and refer to those for your answers: 0.0250 0.0250 0.9750 0.9750 0.9000 x 4.20736 4.73328 5.25920 5.25920 6.31104 5 4 4 CHISQ.INV(av,d) 0.83121 ? 12.83250 ? CHISQ.DISTIX df, 1) 0.62133 ? 0.73828 ? 0.82291 4 5