fig = gcf;
hold on
legend off
lgd = legend('$\mathrm{err}_b(\lambda)$', '$\mathrm{gcv}_b(\lambda)$', ...
       '$\mathrm{err}_v(\lambda)$', '$\mathrm{gcv}_v(\lambda)$', ...
       '$\mathrm{err}(\lambda)$', '$\mathrm{gcv}(\lambda)$', ...
       'Interpreter', 'latex', ...
       'Location', 'best');
lgd.Position = [0.73 0.2 0.1 0.4];
lgd.FontSize = 16;