Berkshire Hathaway Letter

Warren Buffett

According to related descriptions in wikipedia, buffet sold a co-owned business when he was a sophmore (year 1945) in high school for around $1000. If we assume his savings was 10 times of the business he sold 10 years later, then by 1955, his savings would be $10,000. A second description in wikipeida stated that buffet finished college (after 5 years) with a saving of $9,800, which collaborates with our first estimation in terms of magitude. A concervative estimation of buffet's wealth when he founded Buffett Partnership, Ltd would be around $100,000 (around 6.3 Million RMB)

1957 to 1959 Letter

In these three letters, buffett stated an annual portfolio return of 8% to 30% depending on the general market performance (as measured by percentage change of Dow Jones Industry Average). It is unknown whether this return is superior in the investment community at a portfolio size of multi million USD. It is unknown whether a 8% to 30% return is hard to achieve for a fund size of multi thousands USD. My guess is that a higher return (30% to 100%) is achievable assuming certain level of risk.

1957 Letter

In buffet's view, the market is in general priced above intrinsic value. This view relates to blue-chip securities. Buffet stated that if this view is accurate, it is possible that a substantial decline in all stock prices, both overvalued and undervalued, is to happen. As it is very unlikely that current market level will be thought of as cheap 5 years from now. Even a full-scale bear market won't hurt the current work-out portfolio. In buffet's plan, if the general market were to return to an undervalued status, he would invest in the undervalued general issues. It should be noted that, for Buffett at this time, debt financing is an option for the fund needed for general issue investment under this condition. If the general market were to move to a higher level (overvaluation), Buffett plan to put more capital on work-outs.

In Buffett's view, a market decline followed by general decline in earning power is a normal market behavior and it should be. Any market decline not in the same magnitude with the decline in earning power can be considered as "moderate".

Buffett Talks about "current market level", but how does he determine if the current market level is overvalued or undervalued ? Perhaps he was using average PE ratio as a reference to make the judgement.

When dicussing market declines, Buffett use the word "moderate" to describe the market decline in 1957 because the decrease of corporate earning power was worse.
Buffett identify market price, corporate earning power and intransic value as specifically three seperate concept.

I assume that "corporate earning power" refers to the earning power of the company for the next few years. "Intransic" value refers to a longer period, say 30 years.

Does the Buffett position "work-out" stocks before or after corporate action announcement ?

1958 Letter

1958 year, In Mr Buffett's view, is a year with huge number of amateurs entering into the market, pushing up the general market level. The public enthusiasm on stock market will eventually cause trouble, affecting even undervalued stocks. Commonwealth Trust Co. of Union City is the stock our partnerships has large stakes on, we hope its price to remain stable or even decline, so we can purchase more shares for a reasonable price. This would hold back our overall portfolio performance.

Buffett stated that the performance of thier portolio, due to their strategy, would be better in a bear market than in a bull market. He is well statisfied to match the advance of the general market in a bull year.

The partnership has large stake in the Commonwealth Trust Co. of Union City, New Jersey. For reasons including not paying dividends and etcs, the market price for the Comonwealth's stock is $50, while the intransic value of the company is $125 under Buffett's estimation.

The acquiring period of undervalued stock (here Commonwealth Trust Co. of Union City, New Jersey) can be as long as a year. Buffett was building up a position with great patient, buy in shares in good price multiple times.
Buffett chose not to do block trade because of the mangitude of his target position is high, over 10% of target floating shares. Block trade will push up market price for the target stock, which hurt investment return.

1959 Letter

To the extent possible, invest in situations at least partially insulated from the behavior of the general market. This policy should lead to superior results in bear markets and average performance in bull markets. (In modern sense, a low beta, high potential alpha policy. By this policy, an investor can minimize the adverse influence of the general market which he cannot control, therefore the uncertainty of the investment is minimized.)

1977 Letter

  1. Capital Gain
    It is improper to include capital gains and losses when evaluating the performance of a company for a single year, they are an important component of the longer term record.

Buffet admits that

Apache Spark Note

  1. spark-submit提交有第三方依赖的python脚本
    First off, I'll assume that your dependencies are listed in requirements.txt. To package and zip the dependencies, run the following at the command line:

pip install -t dependencies -r requirements.txt
cd dependencies
zip -r ../ .
Above, the cd dependencies command is crucial to ensure that the modules are the in the top level of the zip file. Thanks to Dan Corin's post for heads up.

Next, submit the job via:

spark-submit --py-files
The --py-files directive sends the zip file to the Spark workers but does not add it to the PYTHONPATH (source of confusion for me). To add the dependencies to the PYTHONPATH to fix the ImportError, add the following line to the Spark job,


  1. A JOIN clause is used to combine rows from two or more tables, based on a related column between them.


  1. Share-based compensation (options, etc)
    不消耗公司资金,但增加了流通股数量,降低公司EPS, 同时增大了股票下行压力(被奖励人套现)

  2. FCF (Free Cash Flow) Formula
    FCF = (Sales - OPEXP - DEPEXP)(1-tao) + DEPEXP - Delta WC - CAPEXP

  3. 宏观经济的研究框架

  4. Marketable Securities: Intransic Value v.s. Market Price
    The intransic value of a stock often reveals when negotiated at a merger or acquisition.

  5. Buffet's long-term value investing is under the assumption that excellent business results by corporations will translate over the long term into correspondingly excellent market value and dividend results for owners, minority as well as majority. This assumption is very unlikely to be true for most public companies in China.

  6. Price Volatility can be represented by Coefficient of Variance, which avoids the maginitude effect when using std/variance as measurement. Price Volatility can be compared over an aggregated long-term period, or over the average of the separate daily cov result.

Moreover, the price volatility is shown by observing the daily percentage change of the quote.

Std/Variance or cov is designed to measure a statistical population which may or may not observed from a single entity. When the research objective is a single entity with periodically continueous value (hourly, daily, etc), percentage change is a more understandable measurement.

  1. Non-voting shares as the certificate of beneficial interest
    As opposed to controlling interest.

  2. 价值观和评价体系与客观物质环境紧密相关,中西方的贫富差异决定了国内更注重金钱等物质财富的创造和积累,而西方注重文化、体育等非物质财富的创造。在这种背景下,中西方社会群体对个体行为选择的评价方式也产生了极大差异

  3. 赚钱的几种方式:

  4. Bargin Purchase

A typical bargin purchase targets a company for which the future appears neither distinctly promising nor distinctly unpromising. Uncertainty can be avoid by making decisions other than the future growth of the company. In addition, a good bargin purchase only considers company which is unlikely to have a substantialy decline in earning power. Combing the two previous criteria with a bargin price under conservative evaluation of the intranic value, a margin of safty can be established in the investment.

  1. Earning Power
    Earning Power of the Company = EBIT (Earnings excluding interest and taxes)
    Earning Power of common shares = Net Income

  2. G20 Observation

President Xi seems to be short in personal connections with other world learders. One evidence will be the lack of casual conversations while wating for the class photo taking.