把光学软件啊什么的地址全都删掉了~ sorry~

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Monthly Archives: 2013年四月

换了个vps

最近一段时间,差不多有一个月吧,网站一直打不开,反正我这是打不开,在家以及在公司的网络都打不开。能ping通ip,但是网站打开及慢,有可能是之前的ip被墙了还是怎样,于是乎,我就这样好一个月没去管它了。。。

然后这两天放假,而且之前的vps5月初也快到期了,所以就想换一个呗,是想换linode的,不过后来想想我们这就一个小网站,挂个那么好的vps干嘛呢,瞎折腾?正好又看见某家打折。其实打折这个事情是基本上天天说着打折,也想着放个虚拟主机也行吧,至少如果放个香港的虚拟主机的话国内打开速度会快一点,按照一些朋友的说法,流量也倍增啊。总之,就是换到了现在这个vps上,稍微优化了下更新了下,运行起来很不错,顺便把vpn也开了,之前的一个vps还算是国内的比较稳定的有年限的idc了,给发了tk说帮开下vpn要用的一些服务,直接不理我了,服务单也不回话,无语,这也是我不想继续用他们家的vps的原因之一吧。

接下来一段时间有空的话应该会多更新网站。

还有就是最近的雅安地震,只能说是一个噩梦。希望大家坚强加油!

Technology and Invention in Finance

Overview:

Technology and innovation underlie finance. In order to manage risks successfully, particularly long-term, we must pool large amounts of risk among many, diverse people and overcome barriers such as moral hazard and erroneous framing. Inventions such as insurance contracts and social security, and information technology all the way from such simple things as paper, and the postal service to modern computers have helped to manage risks and to encourage financial systems to address issues pertaining to risk. The tax and welfare system is one of the most important risk management systems.

这节课开始讲的一些保险方面的问题,这就是一个风险分摊这样的意思,就是比如很多人买了一个保险,可是真的出事的并不会所有人都出事是吧,那么出事的那个人所遭受的灾难在得到补偿的时候平分到所有买保险的人身上。。。(这个浅显的道理我好像以前没有注意到。。。)然后这里还讲到的一个重要的词就是道德危险,就是说保险这个事上很多在有嫌似诈骗或者说故意为了保险金的事。以及后续的保险的判断上(判断标准确实很难,很多时候。)

后面还有提到的是一个轮子的故事,还有邮票啊什么的,网络。

The Universal Principle of Risk Management: Pooling and the Hedging of Risks

Overview:

Statistics and mathematics underlie the theories of finance. Probability Theory and various distribution types are important to understanding finance. Risk management, for instance, depends on tools such as variance, standard deviation, correlation, and regression analysis. Financial analysis methods such as present values and valuing streams of payments are fundamental to understanding the time value of money and have been in practice for centuries.

 

我记下这些就像课程笔记一样,或者说我不想看过了然后过了几天就忘了,想要记起一些东西来还得去重看那么一段视频。

这节课主要讲的是高数里面的概率这个东西,如果你是学数学或者比较了解的话会好懂很多。这里截取一些课程pdf里面的公式,其实我是比较懒,虽然wordpress我也有装一些能显示公式的插件,但还是截屏比较方便。然后,WLW确实是一个好东西,离线博客编辑,谁用谁知道。哈哈~

这节课的后面有些忘记了。前几天看的没想写下来,现在想记起来有些难。。。所以说,好记性不如烂笔头。。。是这么说的么。

Probability P, 0<P<1
• Multiplication rule for independent events: Prob(A and B) = Prob(A)*Prob(B)
• Probability of n independent accidents = P^n
• Probability of x accidents in n policies (Binomial Distributon):    

f(x) = {P^x}{(1 - P)^{(n - x)}}n!/(x!(n - x)!)

Expected Value, Mean, Average

9674609

Variance and Standard Deviation

• Variance (^2)is a measure of dispersion
• Standard deviation is square root of variance

9867062

Covariance
• A Measure of how much two variables move together

9921000

Correlation
• A scaled measure of how much two variables move together

10003640

Present Discounted Value (PDV)
• PDV of a dollar in one year = 1/(1+r)
• PDV of a dollar in n years = 1/(1+r)^n
• PDV of a stream of payments x1,..,xn

10137890

Consol and Annuity Formulas
• Consol pays constant quantity x forever
• Growing consol pays x(1+g)^(t-1) in t 
• Annuity pays x from time 1 to T

10206656