pergram.hlp

是一个经济学管理应用软件 很难找的 但是经济学学生又必须用到

{smcl}
{* 31mar2005}{...}
{cmd:help pergram}{right:dialog:  {bf:{dialog pergram}}}
{hline}

{title:Title}

{p2colset 5 21 23 2}{...}
{p2col:{hi:[TS] pergram} {hline 2}}Periodogram {p_end}
{p2colreset}{...}


{title:Syntax}

{p 8 16 2}
{cmd:pergram}
{varname}
{ifin}
[{cmd:,}
{it:options}]

{synoptset 21 tabbed}{...}
{synopthdr}
{synoptline}
{syntab:Main}
{synopt:{opth gen:erate(newvar)}}generate {it:newvar} to contain the raw
periodogram values{p_end}

{syntab:Plot}
{synopt:{it:{help cline_options}}}affect rendition of the plotted points
connected by lines{p_end}

{syntab:Add plot}
{synopt:{opth "addplot(addplot_option:plot)"}}add other plots to the generated
graph{p_end}

{syntab:Y-Axis, X-Axis, Title, Caption, Legend, Overall}
{synopt:{it:{help twoway_options}}}any options other than {opt by()} documented in {bind:{bf:[G]} {it:twoway_options}}{p_end}
{p2coldent:+ {opt nograph}}suppress the graph{p_end}
{synoptline}
{p 4 6 2}+ {opt nograph} is not shown in the dialog box.{p_end}
{p 4 6 2}
You must {helpb tsset} your data before using {opt pergram}.
In addition, the time series must be dense (nonmissing and no gaps in the time
variable) in the specified sample.
{p_end}
{p 4 6 2}
{it:varname} may contain time-series operators; see {help tsvarlist}.
{p_end}


{title:Description}

{pstd}
{opt pergram} plots the log-standardized periodogram for a dense time series.


{title:Options}

{dlgtab:Main}

{phang}
{opth generate(newvar)} specifies a new variable to
contain the raw periodogram values.  Note that the generated graph
log-transforms and scales the values by the sample variance and then truncates
them to the [-6,6] interval before graphing them.

{dlgtab:Plot}

{phang}
{it:cline_options} affect the rendition of the plotted points connected
by lines; see {it:{help cline_options}}.

{dlgtab:Add plot}

{phang}
{opt addplot(plot)} adds specified plots to the generated
graph; see {it:{help addplot_option}}.

{dlgtab:Y-Axis, X-Axis, Title, Option, Legend, Overall}

{phang}
{it:twoway_options} are any of the options documented in
{it:{help twoway_options}}, excluding {opt by()}.  These include options for
titling the graph (see {it:{help title_options}}) and saving the graph to disk
(see {it:{help saving_option}}).

{pstd}
The following option is available with {opt pergram} but is not shown in the
dialog box:

{phang}
{opt nograph} prevents {opt pergram} from constructing a graph.


{title:Examples}

{phang}{cmd:. webuse lynx2}{p_end}
{phang}{cmd:. pergram lynx}{p_end}

{phang}{cmd:. set obs 100}{p_end}
{phang}{cmd:. generate t = _n}{p_end}
{phang}{cmd:. tsset t}{p_end}
{phang}{cmd:. generate y = 5*cos(2*_pi*t/20) + cos(2*_pi*t/10) + cos(2*_pi*t/5)}{p_end}
{phang}{cmd:. pergram y}{p_end}


{title:Also see}

{psee}
Manual:  {bf:[TS] pergram}

{psee}
Online:  
{helpb corrgram},
{helpb cumsp},
{helpb tsset},
{helpb wntestb}
{p_end}