Hi Bert, Tnx for taking time to reply. For clarification... the data do EXPLICITLY indicate when each species is active and when a feeding buzz is recorded. That is ALL it provides based on acoustic data recorded in the field. Only when a species is recorded is it identified as active. How this is accomplished is of no importance to the question I asked.
Note this is Not "individuals" per se. but species as a group. I appreciate you taking time to reply. Clearly this is not a simple solution to what I assumed to be a simple question. Restated as... *How best to use R to calculate occurrence of event( (A) over time vs all events (b...n) over the same time period give the data frame work I have.* Cheers, Bruce > I will not get into your explanation of details that, like John, I > find opaque. Please DO read Hadley's manifesto, as it appears that you > need to organize your data more appropriately. > > AFAICS, however, strictly speaking your data cannot answer the > question you have posed. **Strictly speaking** to know the proportion > of active time bats spend feeding, **for each bat** you would need to > know when it is active and when it is feeding during that time. You > could then summarize this for all bats (e.g. take the average or > median proportion) in a species or whatever. As you cannot identify > individual bats in your data, you cannot do this -- i.e. you cannot > answer your question. > > So the question then becomes: precisely **how** exactly do you propose > using the data you have to determine when a *group* of bats are active > and when they are feeding? How are the groups explicitly identified > and how are their times active and feeding determined? In short, you > need to have information that is something like: > > Bat.Group date active.time.start active.time.end > feeding.time.start feeding.time.end > > ( for a given date and bat group, there may be many multiple entries; > perhaps for a given group, date, and active time start and end, > several feeding time start/stop entries ( I have no idea how bats > behave)). > > Until you can expicitly explain how your data can generate such > information, I think it will be difficult/impossible to help you. > > Cheers, > Bert > [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.