The origin of this problem was that a plain scatter plot with too many
points with high dispersion generated too many points flying all over
places.

We are trying to smooth the charts a bit...

Any good recommendations?

Thanks a lot!

On Fri, Mar 9, 2012 at 8:59 PM, Michael <comtech.usa@gmail.com> wrote:

> Sorry for the confusion Michael.
>
> I myself am trying to figure out what my boss is requesting:
>
> I am certain that I need to "plot the quantiles of each bin.  " ...
>
> But how are the quantiles plotted? Shall I specify 50% quantile, etc?
>
> Being a diligent guy I am trying my hard to do some homework and figure it
> out myself...
>
> I thought there is a standard statistical prodedure that everybody knows...
>
> Any more thoughts?
>
> Thanks a lot!
>
>
> On Fri, Mar 9, 2012 at 8:51 PM, R. Michael Weylandt <
> michael.weylandt@gmail.com> wrote:
>
>> On Fri, Mar 9, 2012 at 9:28 PM, Michael <comtech.usa@gmail.com> wrote:
>> > Thanks a lot Mike!
>> >
>>
>> Michael if you don't mind. (Though admittedly it leads to some degree
>> of confusion in a conversation like this)
>>
>> > Could you please explain your code a bit?
>>
>> Which part?
>>
>> >
>> > My imagination is that for each bin, I am plotting a line which is the
>> > quantile of the y-values in that bin?
>>
>> Oh, so you want a qqnorm()-esque line? How is that like a scatterplot?
>>
>> ....yes, that's something else entirely (and not clear from your first
>> post -- to my ear the "quantile" is a statistic tied to the [e]cdf)
>> This is actually much easier in ggplot (and certainly doable in base
>> as well)
>>
>> Try this,
>>
>> DAT <- data.frame(x = runif(1000, 0, 20), y = rnorm(1000)) # Not so
>> volatile this time
>> DAT$xbin <- with(DAT, cut(x, seq(0, 20, 5)))
>>
>> library(ggplot2)
>> p <- ggplot(DAT) + facet_wrap( ~ xbin) + stat_qq(aes(sample = y))
>>
>> print(p)
>>
>> If this isn't what you want, please spend some time to show an example
>> of the sort of graph you desire (it can be a bit of code or a link to
>> a picture or even a hand sketch hosted somewhere online)
>>
>> Out on a limb, I think you might really be thinking of something more
>> like this:
>>
>> p <- ggplot(DAT) + facet_wrap( ~ xbin) + geom_step(aes(x =
>> seq_along(y), y = sort(y)))
>>
>> and see this for more: http://had.co.nz/ggplot2/geom_step.html
>>
>> Michael Weylandt
>>
>> >
>> > I ran your program but couldn't figure out the meaning of the dots in
>> your
>> > plot?
>> >
>> > Thanks again!
>> >
>> > On Fri, Mar 9, 2012 at 7:07 PM, R. Michael Weylandt
>> > <michael.weylandt@gmail.com> wrote:
>> >>
>> >> That doesn't really seem to make sense to me as a graphical
>> >> representation (transforming adjacent y values differently), but if
>> >> you really want to do so, here's what I'd do if I understand your goal
>> >> (the preprocessing is independent of the graphics engine):
>> >>
>> >> DAT <- data.frame(x = runif(1000, 0, 20), y = rcauchy(1000)^2) # Nice
>> >> and volatile!
>> >>
>> >> # split y based on some x binning and assign empirical quantiles of
>> each
>> >> group
>> >>
>> >> DAT$yquant <- with(DAT, ave(y, cut(x, seq(0, 20, 5)), FUN =
>> >> function(x) ecdf(x)(x)))
>> >>
>> >> # BASE
>> >> plot(yquant ~ x, data = DAT)
>> >>
>> >>  # ggplot2
>> >> library(ggplot2)
>> >>
>> >> p <- ggplot(DAT, aes(x = x, y = yquant)) + geom_point()
>> >> print(p)
>> >>
>> >> Michael Weylandt
>> >>
>> >> PS -- I see Josh Wiley just responded pointing out your requirements
>> >> #1 and #2 are incompatible: I've used 1 here.
>> >>
>> >> On Fri, Mar 9, 2012 at 7:37 PM, Michael <comtech.usa@gmail.com> wrote:
>> >> > Hi all,
>> >> >
>> >> > I am trying hard to do the following and have already spent a few
>> hours
>> >> > in
>> >> > vain:
>> >> >
>> >> > I wanted to do the scatter plot.
>> >> >
>> >> > But given the high dispersion on those dots, I would like to bin the
>> >> > x-axis
>> >> > and then for each bin of the x-axis, plot the quantiles of the
>> y-values
>> >> > of
>> >> > the data points in each bin:
>> >> >
>> >> > 1. Uniform bin size on the x-axis;
>> >> > 2. Equal number of observations in each bin;
>> >> >
>> >> > How to do that in R? I guess for the sake of prettyness, I'd better
>> do
>> >> > it
>> >> > in ggplot2?
>> >> >
>> >> > Thank you!
>> >> >
>> >> >        [[alternative HTML version deleted]]
>> >> >
>> >> > ______________________________________________
>> >> > R-help@r-project.org mailing list
>> >> > https://stat.ethz.ch/mailman/listinfo/r-help
>> >> > PLEASE do read the posting guide
>> >> > http://www.R-project.org/posting-guide.html<http://www.r-project.org/posting-guide.html>
>> >> > and provide commented, minimal, self-contained, reproducible code.
>> >
>> >
>>
>
>

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