Gregor GORJANC wrote:
Peter thanks for the response. So the results from hist(mydata) and truehist(mydata, h = .5) are the same. OK, but the sum of densities or intensities, for case that I gave, don't sum to 1 but to 2. Look bellow. I have an example where these density values are also up to 4 and sum to 5 (I have attached the PDF of that plot). This is really frustrating for me. What are actually these intensisties and densities, how are they calculated. Why are they the same? mydata <- c(1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,2,3,4,5) # histogram with frequencies hist(mydata) # histogram with ratios or probabilities hist(mydata, freq = F) # what are that values on vertical axis # lets take a look at values behind x <-hist(mydata, freq = F, plot = F); x # Sum values sum(x$intensities) [1] 2.000000 R > sum(x$density) [1] 2.000000
Well, look at the breaks! Each has with 0.5!!!! Hence the you have to calculate sum(x$density)*0.5 Uwe Ligges
When I think of histogram (the one not with frequencies) I think of gathering records into "some classes" and then divide the number of records in each "class" by total number of all records. This is not the case in hist(). Sorry for being pain in the ..., but this is really weird. Above that R-team is really doing a great job. Thanks for such a good tool! ------------------------------------------------------------------------
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