*! version 1.0.0 07/08/2020

help numodes [STB-38; snp13]

Title

nuamodes -- Counting and estimation of antimodes in density/frequency data (Updated version)

Syntax

nuamodes [if] [in] [, amodes(#)]

Description

nuamodes calculates the number of antimodes of a density estimation or a
frequency distribution and if especified lists their estimated values. The user
must include the variable with the density or frequency values (denvar) and the
corresponding midpoints (midvar). Useful for histogram or kernel density
estimation antimodes determination.

Options

amodes lists the estimated values for each antimode.

Examples

. use bufsnow

With no data in memory

. bandw1 snow

To obtain the kde bandwidth rules as a guide

. warpdenm1 snow, b(5) m(10) k(6) gen(den5 mid5)

Generating density and midpoint values with aprox. 1/2 of "optimal" Gaussian bw

. nuamodes den5 mid5, amodes

Will display the number of antimodes and their estimated values.

References

Haerdle, W. (1991) Smoothing Techniques with Implementation in S.
Springer-Verlag Chapter 2: 43-84; Chapters 1-2: 1-84.
Ortiz-Martinez, E.L., I.H. Salgado-Ugarte and M.P. Velasco de Leon
(2011) Nonparametric classification of fossil gymnosperm's foliar
area. 2011 Mexican Stata Users Group Meeting Proceedings.
Salgado-Ugarte, I.H., M. Shimizu, and T. Taniuchi (1993) snp6: Exploring
the shape of univariate data using kernel density estimators. Stata
Technical Bulletin 16: 8-19.
Salgado-Ugarte, I.H., M. Shimizu, and T. Taniuchi (1995) snp6.1: ASH,
WARPing, and kernel density estimation for univariate data. Stata
Technical Bulletin 26: 23-31.
Salgado-Ugarte, I.H., M. Shimizu, and T. Taniuchi (1995) snp6.2: Practical
Rules for bandwidth selection in univariate density estimation. Stata
Technical Bulletin 27: 5-19.
Salgado-Ugarte, I.H., M. Shimizu, and T. Taniuchi (1997) snp13:
Nonparametric assessment of multimodality for univariate data. Stata
Technical Bulletin 38: 27-35.
Scott, D.W. (1992) Multivariate Density Estimation: Theory, Practice,
and Visualization. John Wiley, New York, USA: 317 p.
Scott, D.W. (2015) Multivariate Density Estimation: Theory, Practice, and
Visualization. 2nd. ed. John Wiley, Hoboken, NJ, USA: 350 p.
Silverman, B.W. (1986) Density Estimation for Statistics and Data
Analysis. Chapman and Hall.

Authors

Original version:
Isaias H. Salgado-Ugarte, Makoto Shimizu and Toru Taniuchi
University of Tokyo, Faculty of Agriculture,
Department of Fisheries, Yayoi 1-1-1, Bunkyo-ku
Tokyo 113, Japan.(Fax 81-3-3812-0529)
Updated version:
Isaías H. Salgado-Ugarte & V. Mitsui Saito-Quezada
Laboratorio de Biometría y Biología Pesquera
Facultad de Estudios Superiores Zaragoza
Universidad Nacional Autónoma de México
isalgado@unam.mx

Also see

STB: snp6 (STB-16); snp6.1 (STB-26); snp6.2 (STB-27); snp13 (STB-38)

On-line: help for numodes, warpdenm1, kerneld, bandw1, l2cvwarpy, bcvwarpy