Homework Help: Hazard Rate and Survivor Function

1. Oct 28, 2006

I really doubt that anybody would help me out on this...because by experience, nobody ever replies to the stats stuff on this forum...

But i'll try anyway

Question

the hazard rate function is:

h(t) = lamda > 0 ...................... for 0 =< t =< 50

h(t) = lamda + alpha(t - 50) ....... for t> 50

Find the surviovr function S'/S = -h.

So far...all i know is that S = e^-(lamda)t for 0 =< t =< 50

I'm not sure what to do from here...

Can somebody give me a boost please?

2. Oct 28, 2006

Office_Shredder

Staff Emeritus
I would integrate. S'/S = ln(S)'

So calling lamda L and alpha A (I assume they're both constants, right?)
So ln(S) = -(Lt + At2/2 -50At + C) where C is a constant.

In fact, you missed for your other value of S that it's D*e-lamda*t because you didn't do what I did above, and missed the constant of integration