Variant 6

Date: 2015-10-07; view: 427.

We select a sample with volume n=35 from a normal universal set. The standard deviation is is known: σ=20. We find sampling average: =210. We need to verify the null hypothesis =200 using competing hypothesis and confidence level 0.01.

A laboratory made an analysis of 8 samples using 2 methods. The results are shown in the table.

Using confidence level 0.01 verify, if the measurements results differ significantly (we suppose them to be distributed normally)

After 1000 independent tests we found relative frequency 0.33. Using confidence level 0.05 verify a hypothesis: p=0.3, when a competing hypothesis is p>0.3.

Using three independent samples with volumes 19,13,15 items correspondingly selected from normal universal sets we found corrected sampling variances: 3.1, 3.8, 6.2. Using a confidence level 0.05 verify a null hypothesis on homogeneity of variance

X is normally distributed. Sample volume n=55, sampling average =17, the corrected standard deviation s=0.5. Estimate the unknown mean using confident intervals. Reliability g=0.95.