Adam Hayes, Ph.D., CFA, is a financial writer with 15+ years Wall Street experience as a derivatives trader. Besides his extensive derivative trading expertise, Adam is an expert in economics and ...

Julia Kagan is a financial/consumer journalist and former senior editor, personal finance, of Investopedia. Westend61 / Getty Images The annualized income installment method calculates estimated tax ...

When conducting surveys, two kinds of nonresponse may cause incomplete data files: unit nonresponse (complete nonresponse) and item nonresponse (partial nonresponse). The selectivity of the unit ...