两位金融经济学家走进酒吧......在演讲厅前面的那些低悬挂金属杆中的一个，举起音频视频设备。亚慱体育app第一家金融经济学家宣布宣布金融经济学家的能力人群：“我的模型正式预测市场！”房间疯狂，在狂热的掌声中爆发。他在胜利，咧嘴笑着咧嘴笑着。第二届金融经济学家等待人群安静下来，并宣布：“我的模特不仅预测市场......它使市场成为市场！”房间很沉默，足以让悬挂的单词注册。然后...... Pandemonium。第二家经济学家将悬挂在肩膀上，在房间里胜利携带。总而言之，这就是诺贝尔奖品是由......
似乎奇怪的是，我们将奖励科学家们用诺贝尔奖，以便将市场弯曲到他们的模型。但是我们做了无意识。伟大的金融经济学家不只是观察，然后模拟金融市场;在某些情况下，他们实际上可能影响市场函数和行为的方式，并且在某种意义上，他们的理论最终成为自我实现。通常，型号以理论前提开头，即使模型没有，即使模型也没有，即使是缺乏，也要继续存在。但后来，辉煌的金融经济学家不可避免地影响他们正在学习的市场;他们写论文，讲课，博客，电视等谈话等，与那些在市场上使用这些见解的人们分享他们的见解的具体观点。
As a result, some economic models become more precise over time, simply because the masses start to view them as reliable models of economic systems and leverage that knowledge. For example, Millo and Mackenzie show how one of the mainstays of modern finance, the Black Scholes model, changed the very market it was meant to be describing and as a result became more precise.
在这方面,经济学家不像阿斯特朗omers, gazing up and trying to model a starry sky, as the starry sky couldn’t be any more indifferent to the work of the astronomers. It seems highly improbable that an astrophysics model would ever change the nature of the cosmos. Conversely, it is entirely reasonable that financial models and theories would shape the very markets they are meant to explain. Moreover, because financial models are often simplistic representations of the market, the margin for models to effect change in the real world is actually quite great.
每个人都可能同意金融市场的行为 - CAPM，MPT，EMH，MVO，VAR，B-SM等方面的模型 - 是一种高度复杂的系统的优雅抽象。我们证明了我们使用这些模型及其假设，例如有效的市场或理性演员，而不是因为它做出直观的意识，但因为他们简化了一个太复杂而无法理解的世界。与许多宗教帮助人们帮助千年的人们了解我们的起源和我们在宇宙中的地方，简化了未知，“有效市场”和“理性演员”的假设帮助我们以一种有用的方式解释事物经常有效。
And because financial theory, like religion, is far more than an explanation about the world — it’s also a toolkit for operating in this world (e.g., The Ten Commandments) — the financial models that emerge as “true” have profound impacts on all of us. And that can be a good or bad thing depending on the people wielding the models. For the sophisticated, who understand the assumptions and their limitations, economic theories can be profoundly helpful. Others who rely blindly on financial theory without appreciating its problems may be heading down the wrong path.
因此，这是一个重要的话题巨人，因为他们的世界真的被上面列出的金融模式。事实上，他们经常向这些模型的需求弯曲自己的行为，希望有一些洞察这些模型帮助创造的市场。然而，这些模型在根本上仍然有缺陷，并且在稀有危机的时期可能会变得相当不可靠。PabloFernandez最近发表了一份题为“capm：一个荒谬的模型”的文件，他认为：“很明显，Capm的假设和预测/结论在现实世界中没有基础。”Here’s Michel Callon’s take on financial models: “The mathematical models prized by orthodox financial economists are unjustifiable idealizations of the imperfect psychological and institutional realities of markets... Those whose trading activities rely too much on these models will be punished for their naïveté and hubris by practical failure.”
但没有传统的经济学和金融模式，我们会做什么？我们会在一个往往缺乏两者的世界中失去秩序和纪律吗？没有宗教我们会怎么做？我们会失去道德和道德吗？我怀疑我们很好，但我承认没有一个很好的答案。
My views on the matter align more with this perspective: “Hokey religions and ancient weapons are no match for a good blaster at your side, kid.” I invoke the great Han Solo to suggest that we keep our focus on what’s real and practical. We should use the tools we have at hand to understand the world around us. It’s OK for Giants to use the traditional models of finance so long as they understand and recognize the fragility of a system partially built on a modeled reality. They should supplement these abstract tools with others, such as investment beliefs, agent based models, etc. It’s important to remain skeptical and keep grounded in the real economy. But it’s also important to remind yourself that even if these models are based on flawed logic, the markets often reflect that logic. As John Maynard Keynes correctly observed, “Markets can remain irrational longer than you can remain solvent.”