Exercise 3 Consider an experiment to study the resistance to the tension of a machine component. The dataset studies how many breaks occurred during 54 replications of the experiment for two types of material (A and B) and different levels of tension (L = low; M = medium; H = high). To study such relationship we fit a Poisson regression model. The output of the model is the following: (Intercept) Estimate 3.6920 Std. Error z value Pr(>z) 0.0454 81.30 0.0000 material B -0.2060 0.0516 -3.99 0.0001 tension M -0.3213 0.0603 -5.33 0.0000 tension H -0.5185 0.0640 -8.11 0.0000 Null deviance: 297.37 on 53 degrees of freedom Residual deviance: 210.39 on 50 degrees of freedom a) Write the model formulation and assumptions. b) Derive and explain the interpretation of the coefficient associated with the variable "ma- terial B". c) A second model ("model B") assumes that the type of material and the level of tension do not have an impact on the number of breaks. Specify the model and perform a test to compare the model fitted in point (a) with model B.

Exercise 3 Consider an experiment to study the resistance to the tension of a machine component. The dataset studies how many breaks occurred during 54 replications of the experiment for two types of material (A and B) and different levels of tension (L = low; M = medium; H = high). To study such relationship we fit a Poisson regression model. The output of the model is the following: (Intercept) Estimate 3.6920 Std. Error z value Pr(>z) 0.0454 81.30 0.0000 material B -0.2060 0.0516 -3.99 0.0001 tension M -0.3213 0.0603 -5.33 0.0000 tension H -0.5185 0.0640 -8.11 0.0000 Null deviance: 297.37 on 53 degrees of freedom Residual deviance: 210.39 on 50 degrees of freedom a) Write the model formulation and assumptions. b) Derive and explain the interpretation of the coefficient associated with the variable "ma- terial B". c) A second model ("model B") assumes that the type of material and the level of tension do not have an impact on the number of breaks. Specify the model and perform a test to compare the model fitted in point (a) with model B.

Big Ideas Math A Bridge To Success Algebra 1: Student Edition 2015

1st Edition

ISBN:9781680331141

Author:HOUGHTON MIFFLIN HARCOURT

Publisher:HOUGHTON MIFFLIN HARCOURT

Chapter4: Writing Linear Equations

Section: Chapter Questions

Problem 12CR

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