Thanks to Kit Baum an update of the -hangroot- package is now available
from -ssc-. To update type -ssc install hangroot, replace- or
-adoupdate, update-.
This update adds support for the log-normal, Weibull, gamma, Gumbel,
inverse gamma, Wald, Fisk, Dagum, Singh-Maddala, Generalized Beta II,
and the generalized extreme value distribution. -hangroot- can now also
act as a post-estimation command for every package in the -fit-family
except -dirifit- (Because the Dirichlet distribution is a multivariate
distribution and is thus not suitable for being displayed as a hanging
rootogram). A complete list of members of the -fit-family is shown
below.
-hangroot- creates a hanging rootogram (Tukey 1977, Wainer 1974), which
compares a theoretical distribution with an empirical one, by "hanging"
the histogram from the theoretical distribution, instead of "standing"
the histogram on the x-axis. This way deviations are shown as
deviations from a horizontal line (y=0) instead of deviations from a
curve (the density curve). This makes it easier to spot patterns in the
deviations. Also the y-axis is scaled as the square root of the
frequency instead of the frequency to show deviations in the tails more
clearly.
-- Maarten
Tukey, John W. (1977), "Exploratory Data Analysis", Addison-Wesley.
Wainer, Howard. (1974), "The Suspended Rootogram and Other Visual
Displays: An Empirical Validation". The American Statistician, 28(4),
pp. 143-145.
The following packages of the -fit-familily are supported by
-hangroot-. All these packages are available from -ssc-
dagumfit
fiskfit (available soon)
gammafit
gb2fit
gevfit
gumbelfit
invgammafit
invgaussfit
lognfit
weibullfit
smfit
-----------------------------------------
Maarten L. Buis
Department of Social Research Methodology
Vrije Universiteit Amsterdam
Boelelaan 1081
1081 HV Amsterdam
The Netherlands
visiting address:
Buitenveldertselaan 3 (Metropolitan), room Z434
+31 20 5986715
http://home.fsw.vu.nl/m.buis/
-----------------------------------------
__________________________________________________________
Sent from Yahoo! Mail - a smarter inbox http://uk.mail.yahoo.com
*
* For searches and help try:
* http://www.stata.com/support/faqs/res/findit.html
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
