HW4.R

Allison Gonzales — Nov 4, 2013, 4:46 PM

##1.1 
OR=function(x){
  a=1
  b=2
  c=3
  d=4
  oddsratio=(a*d)/(b*c)
  list(data=x, odds.ratio=oddsratio)
}
OR(x)

Error: object 'x' not found

RR=function(x){
  a=1
  b=2
  c=3
  d=4
  riskratio=((a/(a+b))/(c/(c+d)))
  list(data=x, risk.ratio=riskratio)
}
RR(x)

Error: object 'x' not found

##1.2 
dat<-matrix(c(1,2,3,4),2,2)

myOR=function(x){
aa=dat[1,1]
bb=dat[1,2]
cc=dat[2,1]
dd=dat[2,2]
crossprod.OR=(aa*dd)/(bb*cc)
list(data=x, odds.ratio=crossprod.OR)
}
myOR(dat)

$data
     [,1] [,2]
[1,]    1    3
[2,]    2    4

$odds.ratio
[1] 0.6667

myRR=function(x){
  aa=dat[1,1]
  bb=dat[1,2]
  cc=dat[2,1]
  dd=dat[2,2]
  prod.RR=((aa/(aa+bb))/(cc/(cc+dd)))
  list(data=x, risk.ratio=prod.RR)
}
myRR(dat)

$data
     [,1] [,2]
[1,]    1    3
[2,]    2    4

$risk.ratio
[1] 0.75