There are many sources of stock price data. The following are a few illustrative feeds with which your authors are familiar:
• Thomson Reuters Machine Readable News
These sources are described subsequently.
Desirable Characteristics of Datafeeds
To be really useful, a source of price or information data should have the following characteristics:
• Historical as well as current data. Without historical price data, there will be no way to evaluate or backtest strategies.
• Free of survivor bias. The data should include stocks that died or were delisted, so as to avoid survivor bias, and permit testing of predictions of demise.
• Ease of integration and use. The data ...