C www-awu.aleks.com/alekscgi/x/Isl.exe/10_u-igNslkr7j8P3jH-IBcSun54m4HsoQggFsejpgqKoyrQrB2dKVANCOBQYdvpNqDsDNhodWbArCeRDv-bnhK4Uwmc3-WPsi... CONFIDENCE INTERVALS AND HYPOTHESIS TESTING Mayra Confidence interval for the population mean: Use of the t... QUESTION Learning Page A certain brokerage house wants to estimate the mean daily return on a certain stock. A random sample of 18 days yields the following return percentages. -0.43, -1.27, 1.6, -2.56, -2.96, -0.36, -1.82, -1.85, 1.76, 2.01, -2.11, 1.99, 2.98, 1.31, -2.64, 1.68, 1.76, 2.88 Send data to calculator. If we assume that the returns are normally distributed, find a 95% confidence interval for the mean daily return on this stock. Then find the lower limit and upper limit of the 95% confidence interval. Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place. (If necessary, consult a list of formulas. ) Lower limit: Upper limit: OC EXPLANATION We are interested in estimating the population mean u. From the random sample, our estimate for the value of u is the sample mean x (which for this sample is 0.109). Of course, this is only an estimate, and it may or may not be close to the true value of u. To get an idea of the precision of the estimate x, we can construct an interval of values based on