1 The total project cost for a Trex deck ranges between $1,500 and $2,200 for a 250sf deck. 2  Trex Select of basic quality averages approximately $7/sf.  Trex Enhance of higher quality is approximately $8/sf.
When the hypothesized value is zero then there is a simple relationship between hypothesis testing and confidence intervals: If the interval contains zero then the null hypothesis cannot be rejected at the stated level of confidence. If the interval does not contain zero then the null hypothesis can be rejected.
3. Determine how unusual your data must be before it can be considered significant. Many statisticians consider being 95% sure that the null hypothesis is false as a minimum for statistical significance (giving a p-value of 0.05).This is the confidence level.. Determine how unusual your data must be before it can be considered significant. Many statisticians consider being 95% sure that the null hypothesis is false as a minimum for statistical significance (giving a p-value of 0.05). This is the confidence level.