SPH 247 Statistical Analysis of Laboratory Data 1

Exercise 1You have a clinical study in which 10

patients will either get the standard treatment or a new treatmentRandomize which 5 of the 10 get the new

treatment so that all possible combinations can result. Use Excel or R or another formal randomization method.

Instead, randomize so that in each pair of patients entered by date, one has the standard and one the new treatment (blocked randomization).

What are the advantages of each method?Why is randomization important?

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SPH 247 Statistical Analysis of Laboratory Data 2

Exercise 2Analyze the testosterone levels from Rosner’s

endocrin data set in the same way as we did for the estradiol levels, using anova(lm())

Reanalyze estradiol and testosterone using lme() and verify that the results are the same. Here is the specificationlme(Testosterone ~ 1, random = ~1 | Subject,data=endocrin)

Repeat the analysis of the coop data for specimens 2 and 5 separately. Do the analysis both with the traditional ANOVA tables using lm() and with lme() and compare the results

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SPH 247 Statistical Analysis of Laboratory Data 3

Data SourcesThe coop data is from the MASS library

(Modern Applied Statistics in S)The folate data and the enalaprilat data are

from ISwR (Introductory Statistics with R)Estradiol data are from RosnerFasting blood glucose from Andrews and

Herzberg, Data, with the data on Statlib athttp://lib.stat.cmu.edu/datasets/Andrews/

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SPH 247 Statistical Analysis of Laboratory Data 4

Course Websitehttp://dmrocke.ucdavis.edu

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