My Investment Philosophy

Intransic Value

Intransic value only concerns about the earning power of the business, not including the growth potential. Value investing is about buying at a bargin price (compared to intransic value) with enough margin of safety. Invest in certainty.

Investing in growth potential is speculation and add more factors on top of the intransic value and current price level (bargin or not). More factors, higher uncertainties.

Evaluation of An entities'ability to pay back debt

  1. The ability to service debt interest

EBIT/Interest Payment
Net Cash Inflow/Interest Payment
2. The ability to service debt principle

Net Income/Debt Principle

Maintaining a long-term short position should be avoided.

  1. As long-term short position does not offer possible dividend income and foregone the trend of long-term economic growth, it should be avoided.

Distinction Between Inflationary Debt Cycle and Deflationary Debt Cycle

Inflationary debt cycle and deflationary debt cycle diffes in the deleveraging phase. Inflationary debt cycle refers to a debt cycle with a deleveraging process that is inflationary. Deflationary debt cycle likewise.


做空的理由是股票价格被严重高估(相对于intransic value),而不是股价即将下跌。

Intransic Value

The discount rate of intransic valuation based on future free cash flow should be based on the risk-free interest rate.

About Short Term Prediction

In most times we do not predict the short-term movement of the price of a specific stock, because it is impossible to make it right in a realible way. Not mention the general market. However, in extreme cases, short-term price movement can be attempted, especially when the stock experience a tremendous price jump (50% upward overnight), or extremely good news was released to the market.

Aside of the conditions mentioned above, the return of speculation on short-term movement either by news or price fluctuation depends on the timing of buy/sale and calculated guess.

Short Term Investment

  1. Short-term investment out of margin of safety
    Short-term short sell = Event driven/News driven, it is very unlikely that the price will go upward in short term. = Margin of safety

  2. 利用市场的价格波动性来获利,即择时反向操作,利用价格波动的必然性,无论涨跌,股票价格的上下波动本身是一个恒定不变的模式。 对优质股来说,价格不会剧烈波动,从而保证了利用波动本身获利的交易策略具有一定的风险可控性。





拼多多 – Research Memo



Money Supply and Interest Rate

Federal Funds Effective Rate

The weighted average of the negotiated federal fund lending rate among banks.

Federal Funds Target Rate

The target federal funds effective rate set by the Federal Open Market Committee.





  1. 需求资金用于投资PPE, 进口原材料,扩大再生产,实现利润增长
  2. 以债务融资为主


  1. 需求资金用于R&D, 市场推广,人员招聘,实现用户量的规模增长,抢占市场,扩大市场占有率,认可亏损换体量
  2. 以股权融资为主



  1. 平均用户游戏活跃时长为1-6个月




Finance Research Resources

Financial Data

Quandl (/ˈkwɑːndəl/) is a platform for financial, economic, and alternative data that serves investment professionals. Quandl sources data from over 500 publishers

Accounting Codification

FASB Codification

Two Sigma Competition


The dataset of Two Sigma Competition is a h5 file. It can be read into a 1,710,756 rows x 111 columns pandas dataframe.

All datapoints are identified by two attributes combined: id + timestamp, both of which are not unique. Id is a financial security and timestamp indicates the time of quote (Y).

In the dataset there are 1424 different ids and 1813 different timestamps. In general, the data point is sampled in a fixed timestamp interval of 750.