Both the judgmental forecast and the DSGE model have an advantage over the purely statistical model, the BVAR, in that the people who produce the Greenbook and Blue Chip forecasts obviously know a lot more than seven time series, and the DSGE model was built to match the data that are being forecast.
The Greenbook forecast is a detailed judgmental forecast that until March 2010 (after which it became known as the Tealbook) was produced eight times a year by staff at the Board of Governors of the Federal Reserve System.
Also, Makridakis (1987) indicated that managers should prepare a separate judgmental forecast, and then objectively combine it with quantitative forecasts, rather than use judgment for the blending process itself.
Econometric and judgmental forecasts were obtained from commercial forecasting agencies.
Then the job of implementing policy might still be straightforward: Policy adjustments, though perhaps not adhering to transparent rules of thumb, could be calibrated from the model or judgmental forecast
, taking into account the inflation objectives and output constraints of the authorities.
Even in a less structured approach, getting more views for a judgmental forecast can be helpful--but beware of group forecasting.
Second, a wide body of literature suggests that judgmental forecasts are likely to be of dubious accuracy.
A manager with years of experience may tend to lean on judgmental forecasts
because of past experience.
are often used when historical data are not available, such as a new and unique capital project.
They found that these judgmental forecasts
were not, in most cases, more accurate than the naive forecast, and the forecasts suffered from both inefficiency and bias.
Armstrong and Collopy (1998) demonstrated how to integrate objective forecasts with judgmental forecasts
to gain more confidence in future forecasts.
The advantages and limitations of economic models and judgmental forecasts
are reviewed, and a process that incorporates features of both is recommended.