To assess the reliability of timber structures and related building design codes, many researchers have studied strength factors of structural lumber. In one such study, three species of Canadian softwood were analyzed for bending strength. Varying numbers of observations were made for each species. Assume all three populations are normally distributed with equal variances. The results are given here: Bending Strength (in MPa) Mean (in MPa) Douglas-Fir 75, 57, 51 61 Hem-Fir 45, 48, 33 42 Species Spruce Pine- 42, 39, 30, 33 37 Fir a) State the null and alternative hypotheses. b) Construct the appropriate ANOVA table. c) Use the ANOVA table from part b) to test whether there is a difference in the mean bending strengths among the three types of wood at the .05 level.

To assess the reliability of timber structures and related building design codes, many researchers have studied strength factors of structural lumber. In one such study, three species of Canadian softwood were analyzed for bending strength. Varying numbers of observations were made for each species. Assume all three populations are normally distributed with equal variances. The results are given here: Bending Strength (in MPa) Mean (in MPa) Douglas-Fir 75, 57, 51 61 Hem-Fir 45, 48, 33 42 Species Spruce Pine- 42, 39, 30, 33 37 Fir a) State the null and alternative hypotheses. b) Construct the appropriate ANOVA table. c) Use the ANOVA table from part b) to test whether there is a difference in the mean bending strengths among the three types of wood at the .05 level.

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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