Want to calculate variance for a time series data of multiple restaurants with number of customers visiting every day.
date name numCustomers
1-Sep-2016 restaurant1 40
2-Sep-2016 restaurant1 30
3-Sep-2016 restaurant1 35
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1-Sep-2016 restaurant2 20
2-Sep-2016 restaurant2 24
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1-Sep-2016 restaurant3 50
3-Sep-2016 restaurant3 45
For a each week, want to find variance in number of customers visiting each restaurant.
i.e. want to first bucketize the data per week. Then sum numCustomers for each restaurant and find variance on calculated sum. For above example need to find variance for [ restaurant1(40+30+35), restaurant2(20+24), restaurant3(50+45) ]
Looked at extended stats aggregation but not sure how this can be utilized here.