NEWxSFC - Interim Summary…as of 02 MAR 2009					AVG SUMSQ				AVG STP					AVG Total Absolute				AVG Absolute				Mean RSQ
Previous Ranks	Rank	Forecaster	Class	Total STN 4casts	Error (")	Error Z	% MPRV over AVG	Rank	4cast (")	Error	Error Z	% MPRV over AVG	Rank	Error (")	Error Z	% MPRV over AVG	Rank	Error (")	Error Z	%MPRV over AVG	Rank	RSQ	RSQ Z	% MPRV over AVG	Rank	Forecaster
2,1,1,1,1	1	donsutherland1	Chief	116	79	-1.025	53%	2	88.2	9.4	-0.550	46%	5	26.96	-1.171	35%	2	1.37	-1.117	35%	2	75.4%	0.926	33%	3	donsutherland1
5,2,2,3,2	2	shanabe	Senior	118	104	-0.743	34%	5	82.5	22.2	0.099	-7%	8	32.77	-0.765	21%	5	1.62	-0.740	19%	5	71.3%	0.895	29%	4	shanabe
10,6,3,4,3	3	Donald Rosenfeld	Senior	136	104	-0.737	34%	4	94.2	12.8	-0.536	18%	4	35.82	-0.660	15%	5	1.56	-0.817	19%	4	62.2%	0.169	3%	6	Donald Rosenfeld
-,-,-,2,5	4	Raven	Senior	131	129	-0.564	27%	5	94.9	18.4	-0.112	8%	7	40.01	-0.438	11%	6	1.83	-0.469	12%	6	63.5%	0.341	8%	7	Raven
-,-,-,5,7	5	herb @maws	Senior	120	131	-0.310	17%	7	78.9	18.2	-0.219	17%	8	36.87	-0.321	10%	7	1.84	-0.319	11%	6	61.4%	0.189	7%	8	herb@maws
8,-,-,8,6	6	Mitchel Volk	Senior	133	172	-0.204	9%	8	115.2	23.6	0.014	-7%	7	45.41	-0.279	7%	7	2.05	-0.244	6%	7	65.7%	0.359	18%	7	Mitchel Volk
4,4,4,7,8	7	TQ	Senior	117	173	0.083	-4%	9	82.3	26.8	0.455	-36%	10	41.53	-0.072	2%	7	2.05	0.095	-1%	8	63.8%	-0.007	-5%	8	TQ
6,5,5,9,9	8	ilibov	Senior	133	203	0.665	-26%	11	81.4	26.3	0.576	-36%	11	49.03	0.833	-19%	12	2.20	0.536	-10%	10	58.4%	-0.350	-14%	10	ilibov
11,8,6,11,10	9	weatherT	Rookie	111	208	0.790	-37%	12	62.6	31.1	0.597	-51%	10	47.28	0.738	-22%	12	2.64	1.172	-37%	12	59.5%	-0.166	-7%	10	weatherT
14,11,10,14,12	10	jackzig	Senior	127	282	0.884	-44%	11	100.2	21.7	0.040	8%	9	60.57	1.042	-31%	12	2.82	0.958	-27%	12	33.6%	-1.427	-43%	12	jackzig

There have been eight (8) snowstorm forecasting Contests to date. Under the ‘two-thirds’ rule…forecasters who have entered at least six (6) forecasts are included in this interim summary.

To qualify for ranking in the Interim and final ‘End-of-Season’ standings…a forecaster must enter at least two-thirds of all Contests.  If a forecaster has made more than enough forecasts to qualify for ranking…only the lowest SUMSQ Z-scores necessary to qualify are used in the computing the average.  IOW…if you made nine forecasts…only your six best SUMSQ Z-scores are used to evaluate your season-to-date performance.  You can think of it as dropping the worse quiz score before your final grade is determined.  The reason we have this rule is to 1) make it possible to miss entering a forecast or two throughout the season and still be eligible for Interim and ‘End-of Season’ ranking and 2) encourage forecasters to take on difficult and/or late-season storms without fear about how a bad forecast might degrade their overall 'season-to-date' performance score(s).

The mean normalized ‘SUMSQ error’ is the Contest/s primary measure of forecaster performance.  This metric measures how well the forecaster/s expected snowfall 'distribution and magnitude' for _all_ forecast stations captured the 'distribution and magnitude' of _all_ observed snowfall amounts.  A forecaster with a lower average SUMSQ Z Score has made more skillful forecasts than a forecaster with higher average SUMSQ Z Score.

The 'Storm Total Precipitation error’ statistic is the absolute arithmetic difference between a forecaster/s sum-total snowfall for all stations and the observed sum-total snowfall. This metric…by itself…is not a meaningful measure of skill…but can provide additional insight of forecaster bias.

The 'Total Absolute error' statistic is the average of your forecast errors regardless of whether you over-forecast or under-forecast. This metric measures the magnitude of your errors.

The 'Average Absolute Error' is the forecaster/s ‘Total Absolute Error’ divided by the number of stations where snow was forecast or observed.

The ‘RSQ error’ statistic is a measure of the how well the forecast captured the variability of the observed snowfall. Combined with the SUMSQ error statistic…RSQ provides added information about how strong the forecaster/s ‘model’ performed.