准版主moontory和majia20112011吵架的神贴～技术or直觉？

BusFin

仁兄，你太有门户之见了，比较同意楼主一些看法，
Asset Pricing 很难做是真的，这是几个tenure professor说的，而且都是数理背景出身
数理的人绝对也喜欢有insight的东西（如B-S model， M-M theorem），没人喜欢trivial的东西

That's definitely not true. Corporate finance is always the core of finance. It has nothing to do with tenure or publications. The reason is that asset pricing questions nowadays are not interesting at all. A paper filled with techniques with no good economic story is never a good paper. I guess that's the difference between your science and social science. For social science, you need a good story to make it a good paper.

仁者见仁， 智者见智吧。存在其合理。

不知道你又怎么解释很多其他学科都要往数学上靠呢， 比如心理学，体育运动学 （我就认识搞这两个方向的PhD）？

在我看来， finance无非是相对比较有吸引力，好多人都在做， 包括一些数学物理背景的， 数学被用到了极致， 以至于超出了finance作为一个应用学科所能承受的。asset pricing 不能成为主流是因为剩下的问题大家都做不动了。corporate finance成为了主流是因为大家还要paper 去拼tenure.  但是谁也不能保证某个大牛某一天又从新将asset pricing 带回主流。只能说目前这个market还不需要这么高深的数学而已。 其实asset pricing 和corporate finance 也不是exclusive的。

好多建模本来就没什么economic intuition，而且不是跟实际社会联系一下就叫有经济直觉了。做asset pricing的多，有一部分原因是由于一大批数学物理背景的人非要往金融上转 然后不自觉就把金融拉到另一个方向。

-- by 会员 lianghao (2010/11/10 18:40:19)

-- by 会员 cwwlys (2010/11/10 21:07:30)

-- by 会员 majia20112011 (2010/11/11 12:45:05)

BusFin

no need to look down at others. everyone can claim that what they are doing is the mainstream, as long as they really enjoy their work and can find other people out there enjoy their work too. Many papers are just bullshit, regardless of the fields. It does not mean the whole field is nonsense. To build up a network, the first lesson is to respect other people, esp their rights to publish bullshit if they can.

BusFin

呵呵，看来科班出身的对physicists转finance的家伙很有看法。
任何领域（包括物理）要发顶级文章，都一定得有让人耳目一新的insight。

兼收并蓄，有容乃大

My point is very simple: there are quite a few papers nowadays which are purely a showoff of techniques without any economic insight. The rest is what you have said. Papers with good economic insight is because their ideas are good and intuitive and their conclusion can be summarized in at most a couple of plain English sentences.  If those idea needs to be illustrated using whatever technique as necessary, then use it. But do not use technique solely for the purpose of showing off something unless you have some real interesting economic story to tell. The art of economic modelling is to illustrate your point using the simplest possible model, although sometimes the simplest possible model might be quite technical. At least this is what I have learnt from Bob Lucas and Ed Prescott.  They write technical papers, but they use technique for good reasons.


I have no idea if the technique in B-S is basic to physicists, but their idea is simple and intuitive and can be expressed in plain English. If that needs to be done in such technical way,  that is fine. You seems to be indicating finance people do not have as much technical skills as physicists. But, rather than derivative pricing, I do not see any physicists making real big contributions to the finance literature (exclude John Cochrane or Steve Ross who has a undergraduate physics degree because their PhD training are solid econ and finance), in particular the corporate finance area. What's more, as somebody in the board pointed out a long time ago (sorry I cannot remember the ID) in recent years most job market stars (especially Chinese) are from traditional finance and econ background and that does contribute to the point that economic intuition and  institutional knowledge are more important than pure technical skills.

Even agreeing what you said (although I do not think Merton's formulation is not quite technical), the spirit of B-S can be summarized in one simple plain sentence without mentioning any of the algebra and that is the spirit. I never look down upon technical stuff. In fact, most of the Econometrica papers are quite technical. However, you need to use technique for a good reason, not just show people how good you are in techniques. All great findings in asset pricing and corporate finance, no matter how technical they might be in appearance, can be summarized in at most a couple of plain sentences without mentioning any of the techniques involved and a good example is Revelation Principle.

-- by 会员 majia20112011 (2011/3/29 2:00:05)

What is your point? When people say some paper are quite technical, it is not necessarily non-sense. In fact you can find many technical paper with great economical insight. Great idea has no significant relationship with the technics  it was illustrated, a very simple idea may need a quite technical model to show, and in many cases some simple and sounds reasonable idea often turns out to be wrong if you model it carefully. B-S model(sorry, it is not Merton's model, though they were related), when it first came out, was quite technical(though basic to physicians) to the Finance academic community that very few people really understood it, you can see many rumors about how the model came out and how ONE of them try to build and solve the model.

-- by 会员 moontroy (2011/3/29 2:24:26)

-- by 会员 majia20112011 (2011/3/29 9:16:03)

BusFin

I really appreciate your posts. No doubt many nice theoretical papers in corporate finance have learned and
borrowed those "showoff" tools which are first employed in asset pricing (see, e.g. zhiguo he's papers).
Technical stuffs are kindof necessary when one needs to express his/her views in a rigorous manner.
Although it is good to put one's (economic, physical, psycological, whatever) intuition into one or two
simple sentences, many many times our common sense or intuition turns out simply wrong.

三人行，必有我师焉

"I agree with your basic point but I may not holding such a strong attitude as you. Start with a great idea and then find a way to model it is a good way to do research, but there are many other possible way to contribute.
There are indeed some very technical papers at their era but without too many fresh economics insight, but they provide some very useful tool for following researches(a not so good example might be theoretical econometrics, they mainly try to solve some problems in applied field, or just theoretical interest, but the solution itself often lack of any economic insight).
There are also many other great works with some intuitions difficult to express in plain sentences, like Arrow's impossibility theorem, in those situations, technical work often provides some results out of people's intuitive thoughts, and it is those technical results which push people to rethink some so called "common sense", and change our view of the world. There are many examples in Micro theories generating those "counter intuitive" results, and many of them are not easy to explain in a very few sentences.
And I think you know that there are many models and famous papers analyzing the same issue but generate totally different results with their own great ideas(like Macro, since you mentioned Lucas and Prescott), and the first step for us to compare them is to understand the technical details.
And even though technical level itself has no direct relationship with the quality of the paper, I would say it is still a not so good indicator of quality of research in different field, the history of economic or finance research in a field is a history of relaxing assumption or finding problems in previous methods, both often requires a more technical method to deal with.


I'm not saying you are wrong, and no offense. I just say technical issue is not a secondary factor as you mentioned, it is a very important part of the research and I would be very cautious to make those statements.

-- by 会员 moontroy (2011/3/29 10:58:18)"

BusFin

"In mathematics or physics, it may well be the case that the more technical, the better."

Let me tell you, this is absolutely not the case. Don't judge other fields like that if you have no research experience or exposure to those solid sciences.
Though I agree with what you intend to stress (intuition, insights, blabla), I don't like your strong attitude toward other things/people. Most mathematicians and physicists I have so far interacted with are very humble people.