[R] weighted average grouped by variables

[Massimo Bressan]

hi thierry 

thanks for your reply 

yes, you are right, your solution is more straightforward 

best 


Da: "Thierry Onkelinx" <thierry.onkelinx at inbo.be> 
A: "Massimo Bressan" <massimo.bressan at arpa.veneto.it> 
Cc: "r-help" <r-help at r-project.org> 
Inviato: Giovedì, 9 novembre 2017 15:17:31 
Oggetto: Re: [R] weighted average grouped by variables 

Dear Massimo, 

It seems straightforward to use weighted.mean() in a dplyr context 

library(dplyr) 
mydf %>% 
group_by(date_time, type) %>% 
summarise(vel = weighted.mean(speed, n_vehicles)) 

Best regards, 



ir. Thierry Onkelinx 
Statisticus / Statistician 

Vlaamse Overheid / Government of Flanders 
INSTITUUT VOOR NATUUR- EN BOSONDERZOEK / RESEARCH INSTITUTE FOR NATURE AND FOREST 
Team Biometrie & Kwaliteitszorg / Team Biometrics & Quality Assurance 
thierry.onkelinx at inbo.be 
Kliniekstraat 25, B-1070 Brussel 
www.inbo.be 

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