A4.pdf - STAT 359\/563 A01(Spring 2018 Assignment 4 Due 1:00pm March 29 1(15 marks One study examined the impact of temperature on the viscosity of

# A4.pdf - STAT 359/563 A01(Spring 2018 Assignment 4 Due...

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STAT 359/563 A01 (Spring 2018) Assignment 4: Due 1:00pm, March 29 1.(15 marks) One study examined the impact of temperature on the viscosity oftoluene-tetralin blends. The data are given in the following table, where temper-ature is measured inoCand viscosity is in mPa·s.Temperature24.935.044.955.165.275.285.295.2Viscosity1.1330.9770.8530.7550.6720.6020.5420.507(a) (6 marks) Plot the data and fit the simple linear regression model. Is thelinear model a good fit for the data? (Include residual analysis here.)(b) (7 marks) Fit a quadratic model. Present the residual analysis and the fittedmodel. Also include the scatter plot with fitted quadratic line.(c) (2 marks) What proportion of the variation in viscosity can be explained bythe quadratic model in (b)?2. (15 marks) The file “growth2.csv” gives data on the height of a white spruce treemeasured annually for 50 years.LettingYt(m) denote the height of the treeat yeart >0, we consider describing the growth of the tree over time with anon-linear modelYt=f(t) +t;ti.i.d. N(0, σ2).Two growth curves are