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help for ^cutv5^                   [STB-49: dm66; STB-50: dm66.1; STB-51: dm66.2]
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Recoding variables using grouped values (Stata 5 version)
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^egen^ newvar = ^cutv5(^varname^),^ ^br^eaks^(^x1,x2,...,xk^)^ [^ic^odes ^lab^el ^g^roup^(^k^)^]
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Description
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The option ^cutv5^ in ^egen^ creates a new categorical variable coded
with the left-hand ends of the grouping intervals specified in
breaks(). It allows short-cuts in specifying the breaks, 
(labelled) integer codes in place of the left-hand ends of the intervals, 
and can produce approximately equal frequency groups.
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Options
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^breaks( )^ supplies the breaks for the groups, in ascending
    order. The list of break points may be simply a list of numbers
    separated by commas, but can also include the syntax a[b]c, meaning
    from a to c in steps of size b. If no breaks are specified the command
    expects the option ^group^.
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^icodes^ requests that the codes 0, 1, 2, etc. be used in place of the
    left-hand ends of the intervals. 
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^label^ requests that the integer coded values of the grouped variable
    be labelled with the left--hand ends of the grouping intervals. Specifying
    this option automatically invokes ^icodes^.
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^group( )^ specifies the number of equal frequency grouping
    intervals to be used in the absence of ^breaks^. Specifying  
    this option automatically invokes ^icodes^. The command works by first
    calculating the appropriate percentiles using the command ^pctile^ and
    then using the percentiles as break points. 
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Example
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Using the variable ^length^ from the ^auto^ data, the commands
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^egen lgrp=cutv5( length),breaks(140,180,200,220,240)^
^tab lgrp^
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produce the output
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       lgrp |      Freq.     Percent        Cum.
------------+-----------------------------------
        140 |         31       41.89       41.89
        180 |         16       21.62       63.51
        200 |         20       27.03       90.54
        220 |          7        9.46      100.00
------------+-----------------------------------
      Total |         74      100.00
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So will the command
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^egen lgrp=cutv5( length),breaks(140,180[20]240)^
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Values outside the range 140--240 are coded as missing. The command
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^egen lgrp = cutv5(length), breaks(140,180[20]240) label^
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will produce a variable coded 0, 1, 2, 3 but labelled
140-, 180-, 200-, 220-. 
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Thus ^tab lgrp^ produces
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       lgrp |      Freq.     Percent        Cum.
------------+-----------------------------------
       140- |         31       41.89       41.89
       180- |         16       21.62       63.51
       200- |         20       27.03       90.54
       220- |          7        9.46      100.00
------------+-----------------------------------
      Total |         74      100.00
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and ^tab lgrp, nolab^ produces
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       lgrp |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |         31       41.89       41.89
          1 |         16       21.62       63.51
          2 |         20       27.03       90.54
          3 |          7        9.46      100.00
------------+-----------------------------------
      Total |         74      100.00
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The commands
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^egen lgrp = cutv5(length), group(4) label^
^tab lgrp^
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will produce
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       lgrp |      Freq.     Percent        Cum.
------------+-----------------------------------
       142- |         17       22.97       22.97
       170- |         20       27.03       50.00
     192.5- |         18       24.32       74.32
       204- |         19       25.68      100.00
------------+-----------------------------------
      Total |         74      100.00
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Authors
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  David Clayton, Biostatistical Research Unit, Cambridge, 
  david.clayton@@mrc-bsu.cam.ac.uk
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  Michael Hills (retired) 
  Imperial College School of Medicine, London, UK
  mhills@@regress.demon.co.uk