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主题:【原创】关于陈经 -- 红绿

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家园 关于经济学的道听途说

我听过经济系的朋友们讨论,都说,经济学本来就是wishful的东西,任何一个经济理论都是给出一大堆前提条件,任何一个条件不符合,结果都可能不成立。。。所以,我觉得不必从严格经济学名词上来考虑官办经济,本来官办经济就是一种西方经济学涉猎不多的东西,而政治经济学大概很难说符合严格的西方经济学的架构。。。

PS,我不是专业人士,不过那些朋友们,勉勉强强是入门的博士。。。

家园 的确他们了解不算多

也不是想象中的少, 欧洲, 澳洲都有国企, 私有化方面的研究一直是重要课题.美国少得多, 所以光从美国情况来看会给人造成一定误解.

经济学虽然解释比预测强, 还有提高余地, 但讲人家纯是wishful就有点伤感情了吧 :)

家园 呵呵,不妨当作他们行里人的自谦

大约是想说,经济学的model都有太多的限制条件,面对的又是整个社会的未知的反应,不像理工科大部分条件都是可控的,所以。。。

wishful我是当期望的意思来用的,不是痴心妄想

家园 你的朋友不错

比较诚实也愿意自我解嘲。我的看法是,量化的经济学差不多在你朋友说的和读本科的信奉者想象的之间。

西方经济学并不是一个封闭的体系。关于政府政策和体制,还有其他譬如贿赂,国际之间的干预等等都有研究,而且是热点,可惜是难点永远是相对客观的观察。

对经济学的无能,有个法国的物理学家/经济学家有一个essay在本期的自然上,有兴趣可以去看看。简单明了地说了经济学面对的困难和方法论的缺陷。

Financial engineers have put too much faith in untested axioms and faulty models, says Jean-Philippe Bouchaud. To prevent economic havoc, that needs to change. Economics needs a scientific revolution

Compared with physics, it seems fair to say that the quantitative success of the economic sciences has been disappointing. Rockets fly to the Moon; energy is extracted from minute changes of atomic mass. What is the flagship achievement of economics? Only its recurrent inability to predict and avert crises, including the current worldwide credit crunch.

Why is this so? Of course, to paraphrase Isaac Newton, modelling the madness of people is more difficult than modelling the motion of planets. But statistical regularities should emerge in the behaviour of large populations, just as the law of ideal gases emerges from the chaotic motion of individual molecules. To me, the crucial difference between modelling in physics and in economics lies rather in how the fields treat the relative role of concepts, equations and empirical data.

Classical economics is built on very strong assumptions that quickly become axioms: the rationality of economic agents (the premise that every economic agent, be that a person or a company, acts to maximize his profits), the 'invisible hand' (that agents, in the pursuit of their own profit, are led to do what is best for society as a whole) and market efficiency (that market prices faithfully reflect all known information about assets), for example. An economist once told me, to my bewilderment: "These concepts are so strong that they supersede any empirical observation." As economist Robert Nelson argued in his book, Economics as Religion (Pennsylvania State Univ. Press, 2002), the marketplace has been deified.

Classical economics has no framework through which to understand 'wild' markets.Physicists, on the other hand, have learned to be suspicious of axioms. If empirical observation is incompatible with a model, the model must be trashed or amended, even if it is conceptually beautiful or mathematically convenient. So many accepted ideas have been proven wrong in the history of physics that physicists have grown to be critical and queasy about their own models.

Unfortunately, such healthy scientific revolutions have not yet taken hold in economics, where ideas have solidified into dogmas. These are perpetuated through the education system: students don't question formulas they can use without thinking. Although numerous physicists have been recruited by financial institutions over the past few decades, they seem to have forgotten the methodology of the natural sciences as they absorbed and regurgitated the existing economic lore.

The supposed omniscience and perfect efficacy of a free market stems from economic work done in the 1950s and 1960s, which with hindsight looks more like propaganda against communism than plausible science. In reality, markets are not efficient, humans tend to be over-focused in the short-term and blind in the long-term, and errors get amplified, ultimately leading to collective irrationality, panic and crashes. Free markets are wild markets.

Picture imperfect

Reliance on models based on incorrect axioms has clear and large effects. The Black–Scholes model, for example, which was invented in 1973 to price options, is still used extensively. But it assumes that the probability of extreme price changes is negligible, when in reality, stock prices are much jerkier than this. Twenty years ago, unwarranted use of the model spiralled into the worldwide October 1987 crash; the Dow Jones index dropped 23% in a single day, dwarfing recent market hiccups. Ironically, it was the very use of a crash-free model that helped to trigger a crash.

This time, the problem lies, in part, in the development of structured financial products that packaged subprime risk into seemingly respectable high-yield investments. The models used to price them were fundamentally flawed: they underestimated the probability that multiple borrowers would default on their loans simultaneously. These models again neglected the very possibility of a global crisis, even as they contributed to triggering one.

Surprisingly, classical economics has no framework through which to understand 'wild' markets, even though their existence is so obvious to the layman. Physics, on the other hand, has developed several models that explain how small perturbations can lead to wild effects. The theory of complexity shows that although a system may have an optimum state, it is sometimes so hard to identify that the system never settles there. This optimum state is not only elusive, it is also hyper-fragile to small changes in the environment, and therefore often irrelevant to understanding what is going on. There are good reasons to believe that this paradigm should apply to economic systems in general and financial markets in particular. We need to break away from classical economics and develop completely different tools. Some behavioural economists and econo-physicists are attempting to do this now, in a patchy way, but their fringe endeavour is not taken seriously by mainstream economics.

While work is done to enhance models, regulation also needs to improve. Innovations in financial products should be scrutinized, crash-tested against extreme scenarios outside the realm of current models and approved by independent agencies, just as we have done with other potentially lethal industries (chemical, pharmaceutical, aerospace, nuclear energy).

Crucially, the mindset of those working in economics and financial engineering needs to change. Economics curricula need to include more natural science. The prerequisites for more stability in the long run are the development of a more pragmatic and realistic representation of what is going on in financial markets, and to focus on data, which should always supersede perfect equations and aesthetic axioms.

家园 觉得楼主讲的很客观,没什么对陈经的不尊重呀!

难道有和陈经不同的观点都不能提了么?顺便说一下,我也非常佩服陈经。

家园 研究经济可能需要借鉴教育孩子的方法

幼儿心理学有用吗?当然有。但是,每个孩子都是不同的,即使是同卵多胞胎,性情都有差异,有的随和,有的倔强;有的冲动,有的沉稳,不一而足。

所以,老邓是仅次于老毛的牛人,“一摸二猫”,走出了中国的强国之路。

家园 陈经的同意者说话的声音比较大而已

我也来说几句废话。这里大多都是陈经的同意者,我也不期望能改变什么,只是偶尔来说几句不吐不快的话

陈大的不同意者,大都因为态度不好,言辞不够尊敬,或者动机有问题,给赶走了或者干脆直接封了.呵呵.

不过你还好,只给人发现错别字多而已

家园 此帖有寶,謝謝樓主

恭喜:你意外获得【通宝】一枚

鲜花已经成功送出。

此次送花为【有效送花赞扬,涨乐善、声望】

家园 作者意外获得【通宝】一枚

恭喜:你意外获得【通宝】一枚

谢谢:作者意外获得【通宝】一枚

鲜花已经成功送出。

此次送花为【有效送花赞扬,涨乐善、声望】

家园 事后的批判与评论似乎价值不大

若是当初能够对官办经济和格子组的股票操作提出这类中肯的意见,个人会非常佩服楼主,不过嘛,现在根据股市的沉浮结果来倒推,做些事后的批判与评论,似乎价值不大。个人以为,基于现在的客观现实提一些对将来有帮助的前瞻性的建议远比单纯的事后批判要有价值。建议楼主不妨基于自己的专业能力和独立思考,对今后的股市走向提些自己的见解,甚至对格子组的股票操作提些自己的建议,这样或许更有价值一些。

另外,个人建议不到万不得已,尽量不要点名批判,毕竟说明自己的观点未必非要揪出一个具体的人来当靶子的。不点名的说明自己观点,一方面能够让楼主的观点更容易被河友接受,另一方面也能保持河里融洽的氛围,我想真正吸引广大河友的还是河里的氛围吧。

家园 mark一下

过一段时间回来看看,到底那边更靠谱。

官办经济是我(能)看到的对我国发展解释的最好的文章。

陈经和老郎因为不是所谓的“科班出身”被拍了不少砖头,大都感觉很酸,有你也配姓赵的意思。雷曼科班出身的一堆懂经济、金融、投资的,前不久都回家了,不知道这些拍砖的比他们如何。

其实要酸,也应该酸葡萄去,不就是认识几个“高级内幕”嘛,连独立的分析都少,还那么多人迷信。

家园 【原创】回复以下

这位可以简单查一下我在这里发东西的纪录。首先,老拙的分析我从来就说有价值的。第二,我来这个地方看时,大盘大概4-5000点(如果没记错的话),我就是这么说的,说这个不是要你的佩服,但如果这位要批评我的马后炮嫌疑,务必作些调查先。第三,说别人的名字我看不回伤害什么,至少我是这样行事的。如果一个论坛,一个id叫另外一个id的名字都是禁忌,而且只有如此才能维护‘气氛’,你觉着这样脆弱的生态平衡很健康?叫陈经不意味我对他没有尊敬。当然有朋友一定要叫‘政委’或者‘陈大’才能表达他们的敬意,我不反对。

家园 看看我的短文再说

你认为官办经济是最好的,没问题。

但是我问两个问题就是拍赚?就是酸?很多人这样反应,让我觉得没法理解。赫赫

家园 切中要害
家园 你说的这些也很正确,但对官办经济要求有些高

股票操作上,你说的很好。可是我觉得,你对陈经的要求有一些高。

陈经的官办经济,确实提出了一套自己的看法,但上升不到理论的高度。按照你的a,b,c,他当然做不到,但有几个经济学家能做到呢?一个民间人物,写出来的东西,能符合许多人的共鸣,这就足够了

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