We have screens at the ready here to watch what happens when stock in the massive Chinese online commerce operation, Alibaba, starts trading in New York. Shares will start at $68, the top of the company’s range. But while many investors are eagerly diving in, others are advising caution. Plus, as we’ve been hearing, the Scots have voted to stay with the United Kingdom, and this–among other things–has a bearing on interest rates. And as Marketplace celebrates its 25th birthday this year, we are looking at the surprising, sometimes delightful and sometimes destructive ways that prices have changed during that quarter century. Last week, we heard a classical definition of inflation from the Harvard professor who literally wrote the textbook definition. But price changes have many causes and can effect people with varying incomes quite differently. Today, we talk to Dean Baker, co-director of the Center for Economic and Policy Research in Washington.