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Close to time for assigning new observers their K factors

HRHA's picture
Joined: 2010-10-15


We've been monitoring the monthly sunspot counts with a Generlized Loglinear Mixed Model created by Jamie Riggs.  This lets us view the 'raw' Wolf numbers and compare them to the Solar Influences Data Cetner's (SIDC) international sunspot number.  You can see in the attached graph and documentation what the AAVSO raw sunspot numbers look like using this GLMM over the last two years.  

However, when computing the American Relative sunspot number, K-statistics are used for each observer from at least 100 observations.  These estimates will be calculated for adequate-seeing conditions, (either G or E) and when the monthly mean sunspot numbers are high in the current solar cycle.  This last requirment is especially important because if the K-factors are computed when sunspot numbers are low observers tend to 'over count'.  If left unchecked this anamaly will almost certaintly result in artificially high sunspot numbers for the rest of the cycle.  

If you are interested in keeping track of your own K statistic you can download William Wilson's spreadsheet found on this AAVSO page:


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