The paper analyses the options open to monopoly firms that sell software or internet service. We consider customers who have different reservation prices that are rectangularly distributed. The monopoly in general undertakes sustainable price discrimination between customers by producing two...

Maintaining moderate level of income inequality is required for the sake of sustainable economic growth. The question that needs to be addressed is how to accurately measure income inequality. We modify the traditional Gini coefficient by using purchasing power parity (PPP). Usually, the PPP...