x = linspace(0,1,1000); 
r1 = -4*x + 4;
r2 = x + 5; 
r3 = 2*x;
r4 = ones(size(x)); 
r5 = 5*x;

figure; plot( x, [ r1; r2; r3; r4; r5 ] ); 
xlabel( 'Probability of w_1' ); ylabel( 'Bayes Risk' );