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not be available and is certainly not free. Sophisticated systems often incorporate several
different types of data—price, valuation, fundamental, calculated, and economic data. To
facilitate incorporating data and databases in a working system, the product team should
complete a data dictionary and a data map. These documents will eventually be used by
database programmers for Stage 3, the programming of the full working system.14.5.1. Best Practices
● Know your data and buy your data. The best data is data whose errors you under-
stand. Also, do not try to get free data from the Internet, because you will have no
control over when the data changes and what the numbers mean.
● Use one consistent source for fundamental data if at all possible.
● Establish data requirements long before making a purchase.
● Complete a data dictionary and data maps.
● Do not bet the firm on the assurances of the data vendor.14.5. SUMMARY