confidence interval.

Forums: Statistics
Email this Topic • Print this Page

The result x of a stress test is known to a normally distributed random variable with mean (u)new and standard deviation is equal to 1.3 .It is required to have a 95% symmetrical confidence interval for (u)new with total width less than 2. find the least number of test that should be carried out to achieve this.

Topic Stats
Top Replies
Link to this Topic

Type: Question • Score: 0 • Views: 1,285 • Replies: 1

No top replies

@maliha,

Step 1: Find the z score for 95% confidence interval on a two sided distribution. I think it is 1.96, but you better check both to learn how to do it and because Internet advice is worth what you pay for it.

Step 2: The confidence interval = z * sigma / sqrt(N). If CI = 1 (half of the 2 total width) = 1.96 * 1.3 / sqrt(N) then N = (1.96 * 1.3 / 1) ^ 2 = 6.5 so 7 tests.

0 Replies

confidence interval.

Related Topics

Quick Links

My Account

able2know