Читать книгу Encyclopedia of Chart Patterns - Thomas N. Bulkowski - Страница 18
The Database
ОглавлениеLet me tell you about the stocks I used to compile the statistics in this book.
1,396 stocks were used; most start in July 1991 and extend into 2020.
Not all stocks covered the entire period.
Some stocks no longer trade. It's important to include what happens when a company goes bankrupt or merged out of existence.
All stocks use daily price data, not intraday, but some chapters use weekly or monthly data.
Most chart patterns were added in real time as new data arrives each day. This avoids look‐ahead bias (where I only catalog patterns I can see have done well).
The real‐time addition of data was done for more than 20 years.
All stocks have been split adjusted unless I no longer actively follow them.
When a new stock is added to the database, it may have been dividend adjusted by the data provider. However, I don't adjust stocks I use in my database for dividends.
A stock becomes part of the database provided it trades above $5 a share (usually), isn't thinly traded (I like to see daily volume over 100,000 shares), and the stock has a heartbeat (meaning it has a reasonable high–low yearly trading range).
Market capitalization varies with all three represented (small, medium, and large).
Most stocks chosen are from American companies whose stocks trade on the NYSE or NASDAQ exchanges.