Qualitative
Forecasting Methods
("Judgmental forecasting") 


Subjective Curve Fitting Product Life Cycle Delphi Method Time Independent Technological Comparison 
Quantitative
Forecasting Methods 

Univariate Forecasting Models:
Everything is a function ot time and/or past y Causal Forecasting Models: The observedvalue of x "causes" us to believe that y will be f(x) For example, seeing smoke now (x) causes us to think we will soon see fire (y). "Leading Indicator Models" is a less misleading name for the same thing. 
Types of
Forecasts 

Point Forecasts Prediction Interval Forecasts ("Probabilistic Forecasts diagram") ("Future forecast" really is presnet forecast of future value!) 
Measuring
Forecast Errors 

Forecast Error = actual 
forecasted. a Positive error means the forecast was Too Low! (silly, isn't it?) Bias: It's OK to be too high sometimes and too low other times as long as it averages out. 

Absolute Deviation Mean Absolute Deviation: Being off by 3, plus or minus, is 3 tomes as bad as being off by 1, pluis or minus 

Squared Error Mean Squared Error: Being off by 3, plus or minus, is 9 tomes as bad as being off by 1, pluis or minus 


Absolute Percentage Error Mean Absolute Percentage Error 