Re: doubts

Posted by Kamal on Jun 08, 2009; 3:33am
URL: http://discussion-forum.276.s1.nabble.com/doubts-tp3019376p3041186.html

2006 15

To show quasi concavity use the basic definition
f(x)>=f(x0)

then wtd average of these should be greater than or equal to f(x0)

wts being lambda in between 0 & 1

for quasi convexity apply the above definition for -f

if -f is quasi concave then f will be qusi convex

In the question y<=x implies f(x)>=f(y)

Now the wtd average where the weights run from 0 to 1 will be greater than f(y)

The given function is hence both quasi convex and quasi concave