#### An example of testing the equality of two medians.
#### No censoring.
# ROCnp2(t1=rexp(100), d1=rep(1,100), t2=rexp(120),
# d2=rep(1,120), b0=0.5, t0=0.5)
###############################################################
#### This example do not work on the Solaris Sparc machine.
#### But works fine on other platforms.
###########
#### Next, an example of finding 90 percent confidence
#### interval of R(0.5)
#### Note: We are finding confidence interval for R(0.5).
#### So we are testing
#### R(0.5)= 0.35, 0.36, 0.37, 0.38, etc. try to find
#### values so that testing R(0.5) = L , U has p-value
#### of 0.10, then [L, U] is the 90 percent
#### confidence interval for R(0.5).
#set.seed(123)
#t1 <- rexp(200)
#t2 <- rexp(200)
#ROCnp( t1=t1, d1=rep(1, 200), t2=t2, d2=rep(1, 200),
# b0=0.5, t0=0.5)$"-2LLR"
#### since the -2LLR value is less than
#### 2.705543 = qchisq(0.9, df=1), so the
#### confidence interval contains 0.5.
#gridpoints <- 35:65/100
#ELvalues <- gridpoints
#for(i in 1:31) ELvalues[i] <- ROCnp2(t1=t1, d1=rep(1, 200),
# t2=t2, d2=rep(1, 200), b0=gridpoints[i], t0=0.5)$"-2LLR"
#myfun1 <- approxfun(x=gridpoints, y=ELvalues)
#uniroot(f=function(x){myfun1(x)-2.705543},
# interval= c(0.35, 0.5) )
#uniroot(f= function(x){myfun1(x)-2.705543},
# interval= c(0.5, 0.65) )
#### So, taking the two roots, we see the 90 percent
#### confidence interval for R(0.5) in this
#### case is [0.4457862, 0.5907723].
###############################################
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