Using_t_PDF_to_estimate_mean - 10 9 2.26 16.51 16.51 15.51...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
J. M. Cimbala, September 2006 i x 1 312.2 Column1 2 320.6 3 315.5 Mean 316.4 4 314.1 Standard Error 1.61 5 319.6 Median 315.5 Mode #N/A (Undefined since no repeats) Standard Deviation 3.59 Sample Variance 12.91 Kurtosis -2.33 Skewness 0.18 Range 8.4 Minimum 312.2 Maximum 320.6 Sum 1582 Count 5 (a) 5 number of data points df = 4 degrees of freedom = n - 1 0.05 (95% confidence level) 2.78 Use Excel's TINV function - student's t 3.59 Sample standard deviation (from above) 316.4 Sample mean (from above) 311.94 Minimum predicted population mean 320.86 Maximum predicted population mean (b) +/- limit = 2 Specify the cofidence interval limit (one side)
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 10 9 2.26 16.51 16.51 15.51 2.13 14.66 14.66 13.66 2.16 15.06 15.06 14.06 2.14 14.84 14.84 13.84 2.16 15.06 15.06 14.06 2.14 14.84 14.84 13.84 2.16 15.06 15.06 14.06 2.14 14.84 14.84 13.84 2.16 15.06 15 Example - Using the Student's t Distribution to Estimate a Mean Value and Confidence Interval (This is equal to S /SQRT( n )) n = = t /2 = S = x _bar = min = max = Iteration procedure to estimate the required n : Guess n df = n - 1 t /2 new n ( n = S 2 t /2 2 / limit 2 ) Converged to n =...
View Full Document

This note was uploaded on 07/23/2008 for the course ME 345 taught by Professor Staff during the Spring '08 term at Pennsylvania State University, University Park.

Ask a homework question - tutors are online