Composite decking is increasingly popular, as it requires little maintenance. Options include polyethylene (with an average cost per square foot of $7.82), polypropylene (average cost per square foot, $8.68) and polyvinyl chloride or PVC (average cost per square foot, $7.50 hollow core, $9.48 solid core.) Pros. Composite materials are very durable, and won't splinter or rot.
Two-sample t-tests for a difference in mean involve independent samples or unpaired samples. Paired t-tests are a form of blocking, and have greater power than unpaired tests when the paired units are similar with respect to noise factors that are independent of membership in the two groups being compared.
Variance and standard deviation are statistical tests that can be performed to explain the data found in a certain sample. A sample is a set of numerical data. It usually includes results from a survey or experiment. Variance of the sample measures how far the results are from the expected results.Standard deviation expresses how close the ...ariance and standard deviation are statistical tests that can be performed to explain the data found in a certain sample. A sample is a set of numerical data. It usually includes results from a survey or experiment. Variance of the sample measures how far the results are from the expected results. Standard deviation expresses how close the ...