2015-16 ASCE concrete canoe team. This time, however, we will take
into account the fact that we do not know the population
variance/standard deviation and instead must use the sample values
along with the t-distribution in order to correctly create
confidence intervals or conduct hypothesis tests or carry out a
t-test. The canoe team prepared 5 different concrete mixes, with
different ratios of cement, admixtures, water, etc.; attempting to
maximize strength while minimizing weight. Approximately 5 samples
for each mix were prepared and each sample was then subjected to
compressive and tensile testing to determine the concrete
strength.
1. Calculate 95% confidence intervals for mix 1 twice; once
using the normal distribution and a second time using the
t-distribution. Why is the range for the latter larger than the
former?
2. Last week, you likely found that 2 of the samples met the
design criteria (compressive strength >800 psi, tensile strength
>175 psi). Repeat the hypothesis test for these 2 samples by
correctly using the t-distribution. Are you still confident that
both samples meet the criteria?
3. Mix 2 and 3 seems similar. Conduct a t-test on the means of
both mixes. Are they statistically different?
4. Conduct a t-test on the means of the mixes that were found to
be satisfactory last week. Are they statistically different?
- In This Activity We Will Be Analyzing Data From The 2015 16 Asce Concrete Canoe Team This Time However We Will Take 1 (65.21 KiB) Viewed 31 times