New Year 2001-2002

The primary analyses for New Years 2001-2002 are complete as of January 4th, 2002. All of the current array of active eggs have reported as of this date, with 44 eggs archived on December 31 and on January 1. The formal analyses are based on the fully detailed data, with 1-second resolution. Although a few eggs are not synchronized to the second, their mis-synchronization has only a conservative influence, so all eggs are included in the analyses. The composite across timezones specified in last year's analysis is used again. (The procedure for the composite is the same as signal averaging, say, for evoked potentials.) A simple picture of time differences around the world assumes 24 timezones, but the formal analysis is based on 37 official timezones, from -14 to +12 hours from GMT, including 10 zones with half-hour offsets.

  1. The 10 minute period surrounding midnight, which corresponds to the first of the formal predictions, shows a modest positive trend, with Chisquare = 625.56 on 600 df, p = 0.228. There is a sharp positive incline a few minutes before midnight, but the figure does not differ much from the expected random walk, so we cannot claim strong support for the GCP prediction of a significant deviation on this measure. The following figure shows graphically the data for the formal prediction.

    New Year 
2001-2002 37 epochs, 10 min

  2. The second of the formal predictions for New Years 2001-2002 is based on earlier years, beginning with the prediction of reduced variance near midnight on Y2K. To test it, the variance across eggs was normalized as Z-scores for each second, then plotted. (Last year the squared Z was used, but a comparison showed that the original Z more clearly represented the reduction. This choice requires a Bonferonni adjustment factor of two for multiple analysis. The sequence of Z-scores was smoothed with a running mean (moving average) using a fairly wide window of 240 points, following the precedent of the previous year. As in the 1999-2000 and 2000-2001 analyses, there is quite compelling evidence for an alteration of the variance around midnight. In the present case, as before, the smoothed curve displays a clear reduction of the variance (represented as rescaled Z-scores) around midnight.

    The following figure shows a one-hour period centered on the New Year celebration. The red curve is the running mean of the normalized variance. The smoothing window is 4 minutes wide, and was chosen to replicate the previous year's analysis (exploration shows that it is not the optimal window, but all windows from 1 min to 10 minutes show the same pattern of reduction.) An estimate for the likelihood of the apparent structure cannot readily be made on the basis of theoretical expectations, so a permutation procedure was used.

    The original data represent a superimposition that yields an average for each second across the 37 timezones (signal averaging). The 60 minutes centered on midnight comprises 3600 datapoints. To estimate the likelihood of the variance reduction at midnight, the signal averaged data were randomly permuted 10000 times. The figure shows the original or "true" data in red. There were 73 cases in the distribution of random permutations where the minimum variance was closer to midnight than the original data, corresponding to a probability of p = 0.0073. Another permutation analysis to estimate the frequency of this degree of variance reduction at midnight found that in 10000 cases, almost 1 in 10 (p = 0.129) had a more extreme reduction somewhere in the hour long period surrounding midnight. When the measures of proxmity and degree are combined, the resulting probability is 0.00094, or less than 1 in 1000. Because our prediction was not directional, and Z was used instead of Z² as a selective choice, this must be multiplied by a factor of 4, yielding p = 0.00376.

    New Year 
2001-2002 37 epochs, 4-min, Running Mean Variance

    To examine the difference made by the smoothing window size, several others were explored. All showed a tendency to focus on midnight, and some were even more impressive than that specified for the formal test. The next figure shows the data processed with a 5-minute window. This informal exploration presents a quite striking picture compared with the formally specified 4-minute window, and would have yielded a much more extreme probability.

    New Year 
2001-2002 37 epochs, 5-min, Running Mean Variance

    The feeling of exhuberence that seems nearly universal for the New Year transition was surely damped by the too-recent events of September 11, and the continuing troubles around the world. Many people candidly admitted they simply did not feel like celebrating. Nevertheless, though the outcome of the GCP analyses is not hugely significant, the two pre-planned tests of the hypothesis do have positive results, and that for the variance change around midnight is impressive. The variance graphs in particular indicate a substantial departure from expectation, focused rather precisely around midnight.

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