FinalExamReview, FinalReviewPart2Data. Solutions: FinalReviewSolutionsPart1, FinalReviewSolutionsPart2

Quiz for Th 12/7 & M 12/10: An engineer measured the Brinell hardness of 25 pieces of ductile iron that were subcritically annealed. The resulting data were:

The engineer hypothesized that the mean Brinell hardness of all such ductile iron pieces is greater than 170. Therefore, he was interested in testing the hypotheses:

H₀ : μ <= 170

PracticeExam3, PracticeExam3solutions (word), PracticeExam3solutions (pdf), PracticeExam3solutions (Excel)

PracticeExam2, practice exam 2 excel, Practice Exam I, practice exam I work excel

quizzes
part 1: Excel: 2var_quiz
part 2: R: Use the “prior” and “after” data set in the code from day 4.

prior=c(1.25, 2.94, 2.38, 3.09, 3.41, 3.00, 2.31, 2.93,
        2.98, 3.55, 2.84, 1.64, 3.22, 2.87, 2.37, 1.91)
after=c(2.40, 3.50, 4.49, 3.17, 5.26, 3.22, 2.32, 3.31,
        3.70, 4.70, 4.94, 5.06, 3.22, 3.52, 5.45, 3.40)
plot(prior,after)
pave=mean(prior)
aave=mean(after)
num=length(prior)
pdevs=prior-pave
adevs=after-aave
sum_pdevs2=sum(pdevs^2)
sum_adevs2=sum(adevs^2)
sum_devprods=sum(pdevs*adevs)
r=sum_devprods/(sum_adevs2*sum_pdevs2);r
r^2
B=sum_devprods/sum_adevs2;B
A=aave-B*pave;A

Q4f18

ages=c(21,23,23,29,21,18,28,22,19,21,29,21,24,21,32,23,24,37)
length(ages)
ageTable=table(ages)
barplot(ageTable,xlab="ages",ylab = "frequency", main="bar graph of student ages")

library(ggplot2)
3+3 #simple addtion
qplot(ages1,geom="histogram",binwidth=2)