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help for ^bcvwarp^                                            (STB-27: snp6.2)
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Biased cross-validation for kernel bandwidth selection 
-------------------------------------------------------

     ^bcvwarp^ varname [^if^ exp] [^in^ range] ^,^ ^d^elta^(^#^)^ ^k^ercode^(^#^)^ 
            [^g^en^(^cvval mval hval^)^ ^ms^tart^(^#^)^ ^me^nd^(^#^)^ ^nog^raph graph_options]


Description
-----------

^bcvwarp^ calculates biased cross-validation (BCV) by means of the ASH-WARPing
procedure.  ^bcvwarp^ dispalys a graph of the BCV score and lists the five
lowest biased cross-validation scores with their M and h (bandwidth) values.


Options
-------

^d^elta^(^#^)^ specifies the small bandwidth resulting from the shifting of histo-
    grams to be averaged.  This value is interpreted as the measurement
    accuracy of the observations.

^k^ercode^(^#^)^ specifies the weight function.  Setting ^kercode()^ to 1 specifies
    the quartic (biweight) function, while setting ^kercode()^ to 2 specifies
    the triweight function.

^g^en^(^bcvval mval hval^)^ specifies three new variables to contain the BCV, M,
    and h (bandwidth), respectively.

^ms^tart^(^#^)^ and ^me^nd^(^#^)^ specify the range of M over which the BCV is calculated.
    By default, ^mstart()^ is 1 and ^mend()^ is set to about a third of the range
    of the data.

^nog^raph suppresses the graph.

graph_options are any of the options allowed with ^graph, twoway^.


Remarks
-------

^d^elta, and ^k^ercode, are not optional. If they are omitted, ^bcvwarp^ displays
an error message and exits.


Examples
--------

 . ^bcvwarp snow, delta(1) kercode(2) mstart(15) me(70) xlog xline(35.29)^
 . ^bcvwarp snow, d(1) k(1) gen(cvval1 mval1 bwidth1) nograph^


Authors
-------

        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
        EMAIL:  fes01@@tzetzal.dcaa.unam.mx


Also see
--------

    STB:  STB-27 snp6.2, STB-26 snp6.1, STB-16 snp6
On-line:  help for @bandw@ (if installed), @ksm@