Question

Part 1: Answer these three questions inside of your Word document file: 1. What is a confidence interval? 2. Provide an example of a confidence interval? 3. Why do we need confidence intervals in statistics? Additional information before your start Part 2: Please use the below formula in Excel for developing the combination calculation i.e., the number of ways of choose n numbers k at a time…The Excel formula is =COMBIN(n,k). This will tell you the number of combinations given a number n chosen k at a time. For instance, if you calculated in Excel =COMBIN(49,5) …this will calculate the number of combinations of numbers 1 thru 49 chosen 5 at a time. For instance, 1,2,3,4,5 would be one of those combinations. ] Next, come up with the Probability = 1 / (n chosen k at time ). Note that the denominator is the =COMBIN(n,k) value. Be sure to show your math work in your Word document. Therefore, if you wanted to come up with the probability of winning buy purchasing 4 lottery tickets, given a 49 number lottery where you can choose 5 numbers….here is the calculation that you need to complete: Probability of Winning ( 4 tickets) = 4 / [ COMBIN (49,5) ] Part 2 (answer these questions in your Word document using the definition of probability and the =COMBIN(n,k) formula calculations from Excel): (4) What is the Probability of winning a lottery where you choose 5 out of 49 numbers in a lottery (5) What is the Probability of winning a lottery where you choose 4 out of the 49 numbers in a lottery (6) The probability of choosing 8 of the 49 numbers in a lottery, and (7) the probability of choosing 2 out of the 49 numbers in a lottery. Please also answer the below by research on the Internet and/or using YouTube: (8) What is the difference between a confidence interval and margin of error? (9) What is the difference in calculating a confidence interval and a margin of error calculated?

Answer 1

1. A confidence interval is an interval estimate of population parameters combined with a probability statement by using sample values.
2. We can find the confidence interval for Population mean (µ), Population standard deviation (s), Population proportion (P) etc.
3. Some time we have to make some reasonable probability statement about the unknown parameter in the population, from which the sample has been drawn. This can be done by using technique of confidence interval. Confidence intervals are about risk. They consider the sample size and the potential variation in the population and give us an estimate of the range in which the real answer lies.