讨论张五常的上河定律

个人意见：在个人生活中历史成本往往会发生巨大的作用，虽然正统的经济学课本避讳说历史成本，微观经济跟宏观毕竟还是相差较大的啊，个体的集合不会是个体的简单相加，微观经济现象的确很微妙啊，个体心理学的经济观点也不是拿过诺贝尔奖么，可见个体心理经济学开始被越来越多的人们注意，在一定程度上得到了初步认同。

以下是引用蓝田日暖29在2004-11-13 16:00:27的发言： 是嘛，他说写完经济解释中的上头成本一节，兴奋得不得了，认为解决了一个前人没有解释的现象。不管这个解释的产权了，您认为这个解释合理吗？

个人觉得张五常的这个处理没问题，因为和沉没成本相关联的要素可以看成是供给相对固定的，由于没有直接的市场价格来测度它，所以看成是租金的形式。

从价格变化（或支付变化）选择不灵敏（极端也是一般的所说的形式是选择不变）的意义上，也就是租金定义角度看是对的，但人家一定是在最化大租金吗？张认为各类生产要素支付成本后，是一定没有利润的了，一个企业比另一企业还多那么一点点收益，是对租金的补尝，道理是有一点的，但我觉得不够严谨（也是一种先验论，呵呵），你说呢？

张五常的逻辑是否可以这样理解：如果一个企业比另一个企业多一点点利润，要么来自不完全竞争市场带来的垄断租金，要么是前一个企业有某种特定要素，产生的租金。如果企业禀赋完全一样，面对的市场环境也一样，就不可能出现利润上的差别

不是这样的，张五常已把生产要素一般化，包括企业家能力、垄断能力等等，所以他说的多一点点，除了风落（运气）的外，就是对上头成本的补尝了。

如果这样就很难解释得通了。沉没成本也是有要素依托的，没有无缘无故的成本呀。俺还是认为要么要素是不一样的，要么是存在某种没有指明的要素

区别是沉没成本不能再变动了（从租金角度看），张五常是这个意思，我有把握不会错，呵呵。

他那里是泛指所有企业，或者说是一般意义上的厂商，主要是为了说明一般所谓的利润不存在，多出来的是租金或上头成本的补尝。　

那就对了，张五常已经运用异质假定了

“那就对了，张五常已经运用异质假定了”这怎么说？

In economics and in business decision-making, sunk costs are costs that have already been incurred and which cannot be recovered to any significant degree. Sunk costs are sometimes contrasted with incremental costs, which are the costs that will change due to the proposed course of action. In microeconomic theory, only incremental cost are relevant to a decision. If we let sunk costs influence our decisions, we will not be assessing a proposal exclusively on its own merits.

For example, when you pre-order a movie ticket, the price of the ticket becomes a sunk cost. Even if you decide that you'd rather not go to the movie, there is no way to get back the money you originally paid and you have a sunk cost on your hands. This assumes, of course, that you can't simply return the movie ticket for a refund, and that the odds that you are able to resell the ticket are essentially zero.

Sometimes only part of the price of a purchase ends up being a sunk cost. For example, when you purchase a car, you will be able to resell it later, though you will almost certainly not fetch the original price for it. In this case, your sunk cost with respect to the car at any given time is the difference between how much you originally paid and how much you could sell it for now.

Economists argue that, if you are rational, you will not take sunk costs into account when making decisions. In the case of the movie ticket, there are two possible end results. You will either have:

Paid the price of the ticket and suffered watching a movie that you do not want to see, or; Paid the price of the ticket and used the time to do something more fun.

In either case, you have "paid the price of the ticket" so that part of the decision should cancel itself out. If you regret buying the ticket because you do not think the movie is worth the money then your current decision should be based on whether you want to see the movie at all, regardless of what you have paid for it - just like deciding whether you want to go to a free movie. The economist will suggest that since the latter option only involves you suffering in one way (spent money), while the former involves you suffering in two (spent money plus wasted time), the latter is obviously preferable.

Many people have strong misgivings about "wasting" resources. This is called "loss aversion". Many people, for example, would feel obligated to go to the movie despite not really wanting to, because doing otherwise would be wasting the ticket price; they feel they passed the point of no return. This is sometimes called the Sunk Cost Fallacy. Economists would label this behavior "irrational": It is inefficient because it misallocates resources by depending on information that is irrelevant to the business decision being made.

This line of thinking, in turn, may reflect a nonstandard measure of utility, which is ultimately subjective and unique to the consumer. If you buy a ticket in advance to a movie you find is bad, you have still made a semi-public commitment to watching it. You may feel that you "save face" by sticking it out, a satisfaction you cannot draw if you leave. To leave early is to make your lapse of judgment manifest to strangers, an appearance you may rationally choose to avoid. You may in fact find some amusement in how bad the movie turned out to be, and take pride that you recognise it to be bad.

The idea of sunk costs is often employed when analyzing business decisions. A common example of a sunk cost for a business is the promotion of a brand name. This type of marketing incurs costs that cannot normally be recovered - it is not typically possible to later "demote" one's brand names in exchange for cash. Decisions about future investments, sales or more advertising should be made based on future possibilities, not biased by the recent large investment in the advertising that the company made last year (or even last week).

ReferencesSutton, J. Sunk Costs and Market Structure. The MIT Press, Cambridge, Massachusetts, 1991. Varian, Hal R. Intermediate Microeconomics: A Modern Approach. Fifth edition. New York, 1999. ISBN 0393978303

http://www.wordiq.com/definition/Sunk_cost

[此贴子已经被作者于2004-11-20 9:28:45编辑过]