Table of Contents
TTest
If the standard deviation for the population is known
If the standard deviation of the sample(s) is known then
The t-distribution is slightly different from the normal
The t-distribution depends on sample size
The t-distribution is a function of the degrees of freedom
The NBS produces samples of almost everything including PCB
For a sample size of 10 and a confidence level of 95% (2*0.025)
Our 95% confidence values is a mean of 289 plus or minus 1.3
The chloro fluoro carbons are used to soften foams
The environmental problem causes a search for new foams
But does the new foam material have the right properties
A support fact test is done
The results, 2.55, is better than the conventional’s 1.80 values
Conventional Foam
Ultrafoam
Congenital Foam
Ultra foam
The bounce test is used to measure surface resilience
A bounce of 65% is recorded for the ultra foam
Compared to 50% for conventiional foams
Here is the data for the t test
The results is a very large t value
There is less than a 1% chance that the ultra foam is not better
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Author: Compaq User
Email: Grow@adm.njit.edu
Home Page: http://www-ec.njit.edu/~grow/statisti.htm
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