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Jmsouch
Level I

How do I calculate z-scores at different aggregation levels?

Hello, 

 

How do I use JSL to calculate Z-scores at different levels of aggregation? I am working with cancer mortality data (1999 - 2015) at the county-level. I need to calculate Z-scores to compare each county to the others within a state and all counties within the country. I cannot simply use the standardize function because it automatically takes an average of rates--which is invalid unless the populations are all exactly equal in size. I need to use some variant of the common Z-score formula to replace the mean of the rates for a given state (incorrect) with a mean of an aggregated region (entire state, for example). This is calculated by aggregating the numerator and denominator independently and then dividing:

 

in other words, SUM(All deaths in all counties in state K at year X) / SUM(All people in all counties in State K at  year X) =/= MEAN(Cancer Death Rates) for all counties in State X at time Y. 

 

  • Most critically, in the z-score calculation, the subtrahend in the numerator must reflect an aggregate mean for an entire region, NOT an average of Rates. 
  • The script needs to account for null values in its calculation of N and at different levels of aggregation (Number of counties for WV  for example = 55, number of counties for which data is non-null = 52; number of all counties in the US  = 3141, number of all counties for data is non-null = 2956, for example). 
  • the standardize function cannot be used here because the Jmsouch_1-1582729326586.png is calculated as an average of rates, which is invalid. 

     

 

Jmsouch_0-1582729290983.png

Is there any way to use JSL to accomplish this task efficiently? 

 

@Wendy_Murphrey @Theresa_Utlaut 

 

 

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