To change the price of good X from its initial value pxA, slide the blue px-button in the yellow field. You can restore the applet by clicking on the symbol in the upper right corner.
Made by Dr. Jens Peter Siebel with GeoGebra.
The utility function here has been originally proposed by Spiegel (1994). To my mind Spiegel's function serves the purpose of illustrating Giffenity best, although it lacks concavity in y.
References:
Spiegel, U. 1994. The case of a "Giffen Good", Journal of Economic Education 25, 137 - 147.
Last update: 04/05/2011