I found this in GW's January CET thread.
Missed predictions
If a person participating in the annual CET competition does not make a prediction in any one month (including January) their prediction error for that month will be calculated as follows:
- the upper quartile (75th percentile) of the prediction errors of all the people in the annual competition who did make a prediction for that month will be calculated at the end of the month plus a penalty of 0.4C (to tie in with the penalties for late predictions);
The result of the above calculation will be used as the CET prediction error for any person who misses a prediction in a particular month subject to one further point:
- If, for any person, their average monthly prediction error for all the previous months in the year to date is higher than the 75th percentile of errors (across all entrants), then the person's average prediction error will be substituted instead of the 75th percentile figure. This override is only likely to apply to those people towards the foot of the table who have very made very large errors in previous months and hence is no likely to be of significance to the overall result.
One final important point. If you want to be included in the year long competition you may not miss more than two predictions during a calendar year. If a third prediction is missed that person will be eliminated from the annual competition (otherwise it would mean 25% or more of the annual error being calculated on non-existent predictions which would reduce the credibility of the competition too much). However, that person can continue to make predictions for the purpose of the monthly competition
Originally Posted by: Frank H