Question

uc A study of the surface roughness of coated interior pipe used in oil fields was conducted. The data in micrometers) for 20 sampled pipe sections are reproduced in the table below. Conduct nonparametric test to determine whether the median surface roughness of coated interior pipe, differs from 2 micrometers. Test using a 0.10 2.43 1.80 1.78 2.52 1.25 236 237 2.20 1.34 2.62 Fuldataset 1.44 1.39 1.46 2.37 2.44 2.09 1.57 2.10 2.80 1.64 What are the null and altemative hypotheses? O A. Ho: 1-2 OB. H:9-11 0 ở Hon=11 H:12 H:>11 H: 911 OD. H: 1-2 OE. Ho: 19 OF HO:9 Hn2 H:99 Hn9 What is the best statistic for this test? The test statistic in What is the p-value for this test? (Round to the nearest thousandth as needed.) What is the conclusion for this fest? Ho. There is M evidence to indicate the median surface roughness of coated interior pipe differs from 2 micrometers at 0.10

Answer 1

mean and standard deviation of the sample data given is

Count, N: 20 Sum, Ex: 39.97 Mean, X 1.9985 Variance, s20.23752921052632 Steps 1 S = (x; – 7)?, N-14 i=1 S2 = E(X; - )2 N-1 (2.43 - 1.9985)2 + ... + (1.64 - 1.9985)2 20-1 4.513055 19 = 0.23752921052632 S= V0.23752921052632 = 0.48736968568666

Null Hypothesis: H:n = 2 Alternative Hypothesis: H,:n 2

Test Statistics t-statistic is computed as follows: X-LLO t= 1.9985 - 2 0.4874/20 :-0.014 s/n

Using the P-value approach: The p-value is p= 0.9892, and since p=0.9892 > 0.1, it is concluded that the null hypothesis is not rejected.

Do not reject, is not enough or (insufficient)