Database management Coursework Example | Topics and Well Written Essays - 1750 words

Database management - Coursework Example select distinct Customer.CustNo, Customer.CustFirstName, Customer.CustLastName, Customer.CustBal from Customer, OrderTbl where Customer.CustNo = OrderTbl.CustNo and (OrderTbl.OrdDate between '01-Feb-2007' and '28-Feb-2007); select distinct Customer.CustNo, Customer.CustFirstName, Customer.CustLastName, Customer.CustBal from Customer, OrderTbl where Customer.CustNo = OrderTbl.CustNo and (OrderTbl.OrdDate between #02/01/2007# and #02/28/2007#); select distinct Customer.CustNo, Customer.CustFirstName, Customer.CustLastName, Customer.CustBal from Customer, OrderTbl where Customer.CustNo = OrderTbl.CustNo and month(OrderTbl.OrdDate)=2 and year(OrderTbl.OrdDate)=2007; select distinct Product.ProdNo, Product.ProdName, Product.ProdPrice from Product, OrdLine, OrderTbl where Product.ProdNo = OrdLine.ProdNo and OrdLine.OrdNo = OrderTbl.OrdNo and OrderTbl.CustNo = 'C0954327' and (OrderTbl.OrdDate between '01-Jan-2007' and '31-Jan-2007'); select distinct Product.ProdNo, Product.ProdName, Product.ProdPrice from Product, OrdLine, OrderTbl where Product.ProdNo = OrdLine.ProdNo and OrdLine.OrdNo = OrderTbl.OrdNo and OrderTbl.CustNo = 'C0954327' and (OrderTbl.OrdDate between

Confidence Interval of Proportions Assignment Example | Topics and Well Written Essays - 500 words

Confidence Interval of Proportions - Assignment Example 1) Have you completed the weekly reading assignment? Yes I have. 2) For the first problem, what is the Margin, and what are the lower and upper confidence limits? The margin of error is 0.0568 and the confidence interval is between .2933 and .4067 or simply (29.33% to 40.67%). 3) For the second problem, what is the Margin, and what are the lower and upper confidence limits? The margin of error is 0.03624 and the confidence interval is between .286 and .3585 or simply (28.6% to 35.85%). 4) For the third problem, what is the required sample size? The required sample size is 545. 5) Does the confidence interval estimate vary from sample to sample? Yes it does. A large sample size improves the precision of the confidence interval (Rumsey, 2005). This is because large sample size results to smaller standard errors meaning that the confidence interval will be narrower and clear-cut .As such, the choice of the sample size influences the confidence interval to use. 6) What percentage of all confidence interval estimates contains the true population parameter? The percentage will depend on the confidence level from the given problem or the significance level (alpha) that the researcher has decided to use.