STATS 401 Study Guide - Midterm Guide: Exponential Distribution, Standard Deviation, Independent And Identically Distributed Random Variables
47 views5 pages
Document Summary
It is decided that a second experiment must be performed to obtain a more precise estimate, where the width of the new ci should be around 1 unit. Two plans are being considered: (a) the same instruments will be used (so is not changed), but the sample size is increased. 2 1. 96 / q m/n = 3, so m = 9n, where m is the second sample size. Thus the sample size must increase by a factor of 9. (b) the same sample size will be used, but a more precise instrument will be obtained, decreasing . Thus the new instrument must be 3 times more precise than the old one. 1 (c) suppose changing by a factor of 1/k costs the same as collecting 4k additional samples. Solution: option (b) would be equivalent in cost to running 12 additional sam- ples, while option (a) would require 9 times more samples.