first principal linefirst projecting linefirst projectionfirst quadrantfirst quarterfirst quartilefirst side of an equalityfirst side of equalityfirst twofirst variationfiscal periodfiscal policyfiscal yearfish tail piecefisher behrense distributionfisher z distributionfisher z transformationfissionfitfit curvefit intofitted valuefittingfitting constantsfitting curvefive lemmafive square matrixfixfix upfixedfixed assetfixed assets turnoverfixed budgetfixed charge problemfixed chargesfixed coefficient production functionfixed costfixed fieldfixed interval inventoryfixed lengthfixed order intervalfixed order inventory modelfixed order sizefixed pointfixed point fieldfixed point iterationfixed point methodfixed point of mappingfixed point theoremfixed position layout