黄新飞 《微观经济学》Chapter 7 （更新版）.pptVIP

* Economic vs. Accounting Profits Let’s talk about how an economist measures a firm’s costs and profits versus how an accountant measures them. In this regard, an economist – as opposed to an accountant – will always count not only explicit costs but implicit costs as well. * Opportunity Costs Includes all consequences, whether they reflect explicit monetary transactions or not. The immediate dollar cost of going to a movie instead of reading your economics textbook is the price of the movie ticket. The opportunity cost also includes the possibility of gaining a better understanding of macroeconomics and therefore becoming more successful in business. * Suppose both you and your spouse earn after tax salaries of $45,000 a year as sales representatives for a hospital equipment distributor, but you want to do better. You borrow $20,000 from the bank at 10% interest. You kick in another $30,000 of your own savings that had been earning you $1,500 annually in interest income from your portfolio of bond investments. You also kick out a tenant in the storefront that you own who was paying you $800 in rent per month. A Case of Opportunity Costs * Your own financial capital $ 1,500 Kicking out your tenant 7,200 After tax salaries 90,000 Total $98,700 Accounting profit $90,450 Economic profit -$ 8,250 Category Opportunity Cost You End Up Being Worse Off 生产、成本理论和企业决策 附录 * 生产函数的数值例子 Q=100 2LA Q = output; L = labor; A = land. The production function is a constant-returns-to-scale production function, a special case of the Cobb-Douglas production function. * 346 490 600 692 775 846 316 448 548 632 705 775 282 400 490 564 632 692 245 346 423 490 548 600 200 282 346 400 448 490 141 200 245 282 316 346 6 5 4 3 2 1 0 1 2 3 4 5 6 Constant returns to scale Labor Land * 346 490 600 692 775 846 316 448 548 632 705 775 282 400 490 564 632 692 245 346 423 490 548 600 200 282 346 400 448 490 141 200 245 282 316 346 6 5 4 3 2 1 0 1 2 3 4 5 6 Diminish