{smcl} {* 14oct2016}{...} {hi:help panell} {hline} {title:Title} {phang} {bf:panell} {hline 2} Display panel length for a given set of variables {marker syntax}{...} {title:Syntax} {p 8 17 2} {cmdab:panell} [{varlist}] {ifin} [{cmd:,} {it:options}] {synoptset 20 tabbed}{...} {synopthdr} {synoptline} {syntab:Main} {synopt:{opt su:ppress}}suppress display of panel-specific characteristics{p_end} {synopt:{opth g:enerate(newvar)}}create marker variable {it:newvar}{p_end} {synoptline} {p2colreset}{...} {marker description}{...} {title:Description} {pstd} {cmd:panell} displays individual and overall panel length of a given set of variables of a rectangular longitudinal/panel dataset (also known as time-series cross-section (TSCS) dataset). The output shows how many observations are non-missing for one variable or even a certain combination of multiple variables. This helps the user in getting a detailed overview of the availabilty of observations for models incorporating a single/multiple exogenous variable(s). Additionally, the range of the time frame of each panel is displayed and when panels exhibits gaps (i.e. missing observations that are encased by non-missing observations within a panel) then those gaps are reported. Furthermore, overall characteristics of all panels (e.g. the number of panels, range of time frame, number of panels with observations, etc.) are displayed. {marker options}{...} {title:Options} {dlgtab:Main} {phang} {opt suppress} suppresses the output of panel-specific characteristics. You may want to use this option if the dataset contains a large number of panels. {phang} {opt generate(newvar)} creates a dichotomous marker variable {it:newvar} that marks all observations with available information for all variables in {it:varlist} with 1 (otherwise 0, if missing). {p_end} {marker remarks}{...} {title:Remarks} {pstd} 1. Since {cmd: panell} is exclusively written for use with TSCS datasets, it is necessary to run the {help xtset} command before executing. {p_end} {pstd} 2. The {help datetime display formats} (e.g. yearly, quarterly, monthly) of the time variable assigned in {cmd: xtset} are automatically detected and displayed. If the time variable has no datetime display format assigned, then the integer values of the time variable are shown in the output. {p_end} {pstd} 3. If {it: varlist} contains no variables, all variables within the dataset are taken into account (same as typing {cmd: panell _all}), albeit all string variables will automatically be removed from {it: varlist}. {p_end} {pstd} 4. If the panel identifying variable has value {help labels} assigned, then these labels automatically appear in the output. {p_end} {marker examples}{...} {title:Examples} Setup {phang}{cmd:. use "http://www.stata-press.com/data/r12/union.dta", clear} {phang}{cmd:. xtset idcode year} Single variable with univariate statistics {phang}{cmd:. panell age} Multiple variables, additional generation of a marker variable {phang}{cmd:. panell age grade not_smsa south union black, gen(markervar)} Entire Dataset without details on individual panels {phang}{cmd:. panell, su} {title:Author} {pstd} Jan Helmdag, Department of Political Science, University of Greifswald, Germany