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On the Variations in Personal Equation 
complete period covering from 20 to 22 observations. Without a detailed analysis 
of the separate series, it is not possible to say whether there is a period of this 
order underlying the variations in judgment in all series, or whether this 
periodicity in v/, results from large variations in one or two series ; the diagrams 
of seven of the series, in Figure 11 do not certainly suggest any marked periodic 
variation, and it is possible that the drop at about the 44th and the peak near the 
The horizontal line intersecting each graph gives the mean of the first 50 observations in that series. 
Fig. H. Bisections. Diagrams representing variations in judgment. 
