Could you please solve it with R Programming and kindly provide the code? Many t
ID: 3355743 • Letter: C
Question
Could you please solve it with R Programming and kindly provide the code? Many thanks!
Problem 2: Five teaching assistants for the recitation section of a large basic statistics course were rated by their students with respect to overall ability. The ratings on the five-points scale had the following frequencies: Teaching assistant Scale value 1 (highest) Total 72 20 10 10 24 16 17 18 30 4 65 2.14 4 5 (worst 34 36 43 46 224 Mean 1.53 1.89 1.98 2.13 (x,- 16.4706 21.556 30.9767 33.2174 53.7538 We shall assume that inferences are to be made only to the five instructors; the fixed- effects model should be used. a) Complete the analysis of variance for the hypothesis of equal teaching assistant means. b) Use the Bonferroni methods to determine which instructors are different What are some other contrasts of the sampler means that are "significant" at the 0.05 level? d) What is the contrast with the greatest Scheffé test statistic? Show that the square of that statistic is proportional of the F-ratio of the analysis of variance in (a)Explanation / Answer
R-code for this problem
x1=c(20,10,4,0,0)
x2=c(12,17,6,1,0)
x3=c(14,18,9,2,0)
x4=c(10,24,8,4,0)
x5=c(16,30,14,4,1)
f=as.factor(rep(seq(1,5),each=5))
y=c(x1,x2,x3,x4,x5)
fit=lm(y~f)
a)
summary(fit)
anova(fit)
# here we get p-value = 0.81>0.05 hence we can comment that
#the teaching assistance has no significant difference among them
b)
pairwise.t.test(y,f,p.adjust.method=c("bonferroni"))
# all methods has same effect
c) there is result has prove that no group mean is signignificantly different
from others