U*****e
发帖数: 2882 | 1 经济学建模通常有这样的情形：
假设消费者总数为测度1，如果有一个商品定价为1元，每个消费者购买1个。那么厂商
的总收入是多
少？
简单的计算得到总收入是1，但是这个1不等于1元，而是1元＊总人口。
许多文献和教科书都不明确指出这个量纲的区别。虽然很多时候没有太大的影响，但有
时非常误导。
比如，假设厂商是个垄断者，需要投资x元来生产商品。如果直接定义利润为收入减去
成本，这个x元
就不能大于1，否则利润是负的。但实际上不应该发生这个问题。因为投资x的量纲和收
入1的量纲完全
不同。
不知道大家有没有遇到过这样的问题或者看到过相关文献？谢谢指点。 | s*****a
发帖数: 353 | 2 I do not believe that is a big deal. After all, everything is normalized.
【在 U*****e 的大作中提到】
: 经济学建模通常有这样的情形：
: 假设消费者总数为测度1，如果有一个商品定价为1元，每个消费者购买1个。那么厂商
: 的总收入是多
: 少？
: 简单的计算得到总收入是1，但是这个1不等于1元，而是1元＊总人口。
: 许多文献和教科书都不明确指出这个量纲的区别。虽然很多时候没有太大的影响，但有
: 时非常误导。
: 比如，假设厂商是个垄断者，需要投资x元来生产商品。如果直接定义利润为收入减去
: 成本，这个x元
: 就不能大于1，否则利润是负的。但实际上不应该发生这个问题。因为投资x的量纲和收
| U*****e
发帖数: 2882 | 3 Thanks for the input.
I used to think so. However, it is not that everything is normalized. In
the example I used, the revenue of 1 is after normalization, but not the
price of 1. So a reader may not sure whether the investment cost is
normalized or not.
If I am the only one gets confused, I can live with that. :)
normalized.
【在 s*****a 的大作中提到】
: I do not believe that is a big deal. After all, everything is normalized.
| s*****a
发帖数: 353 | 4 I will think of it this way:
fixed cost is not normalized, or naturally normalized; while total variable
cost is normalized as revenue.
【在 U*****e 的大作中提到】
: Thanks for the input.
: I used to think so. However, it is not that everything is normalized. In
: the example I used, the revenue of 1 is after normalization, but not the
: price of 1. So a reader may not sure whether the investment cost is
: normalized or not.
: If I am the only one gets confused, I can live with that. :)
:
: normalized.
| U*****e
发帖数: 2882 | 5 This is constructive.
In light of your suggestions, I agree in the case of monopoly (or
oligopoly), both fixed and total costs should be normalized. In the case
of continuum of firms, then only aggregate fixed or total costs are
normalized, while individual costs must not be normalized.
As there are models about one dominant firm and many price-taking small
firms, things could be worse.
variable
【在 s*****a 的大作中提到】
: I will think of it this way:
: fixed cost is not normalized, or naturally normalized; while total variable
: cost is normalized as revenue.
| s*****a
发帖数: 353 | 6 When you have a continuum of firms, I believe the costs are not normalized,
but you can still assume the measure of number of firms is 1, as what you
did for consumers.
This technique, I believe, works for an arbitrary number of firms.
Actually think of it this way, in most of the macro models, we talk about
the average variables, like average capital per capita, etc. There we are
doing virtually the same thing: normalize everything so that it corresponds
to only one person, and we are free to t | U*****e
发帖数: 2882 | 7
normalized,
you
about
are
corresponds
one.
That makes sense. But in micro sometimes we need to look at agents
distinct in their sizes. In this case just talking about everything in
average sense is not enough.
【在 s*****a 的大作中提到】
: When you have a continuum of firms, I believe the costs are not normalized,
: but you can still assume the measure of number of firms is 1, as what you
: did for consumers.
: This technique, I believe, works for an arbitrary number of firms.
: Actually think of it this way, in most of the macro models, we talk about
: the average variables, like average capital per capita, etc. There we are
: doing virtually the same thing: normalize everything so that it corresponds
: to only one person, and we are free to t
| s*****a
发帖数: 353 | 8 I agree.
That way you don't employ this technique.
【在 U*****e 的大作中提到】
:
: normalized,
: you
: about
: are
: corresponds
: one.
: That makes sense. But in micro sometimes we need to look at agents
: distinct in their sizes. In this case just talking about everything in
: average sense is not enough.
|
|
