threshold distribution
On Sun, 2009-04-05 at 01:13 -0400, jim holtman wrote:
Here is what I get from using 'fitdistr' in R to fit to a lognormal. The resulting density plot from the distribution seems to be a reason match to the data.
x <- scan()
1: 0.80010 0.72299 0.69893 0.99597 0.89200 0.69312 0.73613 1.13559 9: 0.85009 0.85804 0.73324 1.04826 0.84002 14: 1.76330 0.71980 0.89416 0.89450 0.98670 0.83571 0.73833 0.66549 22: 0.93641 0.80418 0.95285 0.76876 0.82588 27: 1.09394 1.00195 1.14976 0.80008 1.11947 1.09484 0.81494 0.68696 35: 0.82364 0.84390 0.71402 0.80293 1.02873 40: Read 39 items
plot(density(x)) library(MASS) fitdistr(x, 'lognormal')
meanlog sdlog -0.13480636 0.19118861 ( 0.03061468) ( 0.02164785)
lines(dlnorm(x, -.1348, .1911), col='red')
Hi Jim I agree with your solution but my plot result not fine. I obtain same result.
fitdistr(x, 'lognormal')
meanlog sdlog -0.13480636 0.19118861 ( 0.03061468) ( 0.02164785) In plot when I use points (blue) and curve (green) the fit o lognormal and density(data) is fine but when I use lines (red) the fit is bad (in attach I send a PDF of my output) Do you know why this happen? Thanks in advance
Bernardo Rangel Tura, M.D,MPH,Ph.D
National Institute of Cardiology
Brazil
P.S. my script is
x <- scan()
0.80010 0.72299 0.69893 0.99597 0.89200 0.69312 0.73613 1.13559
0.85009 0.85804 0.73324 1.04826 0.84002
1.76330 0.71980 0.89416 0.89450 0.98670 0.83571 0.73833 0.66549
0.93641 0.80418 0.95285 0.76876 0.82588
1.09394 1.00195 1.14976 0.80008 1.11947 1.09484 0.81494 0.68696
0.82364 0.84390 0.71402 0.80293 1.02873
require(MASS)
fitdistr(x, 'lognormal')
pdf("adj.pdf")
plot(density(x))
lines(dlnorm(x, -.1348, .1911), col='red')
points(x,dlnorm(x, -.1348, .1911), col='blue')
curve(dlnorm(x, -.1348, .1911), col='green',add=T)
dev.off()
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