# RE:st:Measuring two time-spells

 From orozco@toulouse.inra.fr To statalist@hsphsun2.harvard.edu Subject RE:st:Measuring two time-spells Date Fri, 25 Jul 2008 08:37:54 +0200

```Dear Jan,

What about generating variables indicating, by date (extracted via the login),
the maximum hour of entry (Max of login) and the minimum hour of entry (Min of
logout) between workers. Then, you can easily calculate the difference of these
two times, which corresponds to the intersection of two workers. Look at this
example with only 2 workers:

minlogout	inter
16-janv-08	1	16/01/2008 13:55	16/01/2008 22:34	16/01/2008 13:55	16/01/2008
22:34	8:38
16-janv-08	2	16/01/2008 07:50	16/01/2008 23:00	16/01/2008 13:55	16/01/2008
22:34	8:38
20-janv-08	1	20/01/2008 14:26	20/01/2008 15:52	20/01/2008 14:26	20/01/2008
15:52	1:25
20-janv-08	2	20/01/2008 10:05	20/01/2008 19:30	20/01/2008 14:26	20/01/2008
15:52	1:25

Hope this helps you.

Valérie

-------------------------------
Valérie OROZCO
Toulouse School of Economics (INRA-GREMAQ)
21, allée de Brienne
F-31000 Toulouse, France

MF 426
+33 5 61 12 85 91
-------------------------------

________________________________________
From	  "Jan Sauermann" <jan.sauermann@gmail.com>

To	  statalist@hsphsun2.harvard.edu

Subject	  st: Measuring two time-spells
Date	  Wed, 23 Jul 2008 18:15:30 +0200
________________________________________
Dear Statalist.

my setting is the following: I observe two workers (i and j) for about
one year. They are at the same workplace; I have information on when
they enter, and when they leave work (my time data is continuous in
seconds). I would like to have a third variable which gives me
information when they are both at the workplace. Eventually, I would
like to have an aggregate variable, e.g. for week 40 of year 2007, how
many hours they have spent together at work.

The main problem is that they have changing shifts and changing number
of hours at one day. I.e., at one day, worker i starts after worker j,
but leaves earlier; another day, i starts first and leaves first. It
can also be more complicated if i has a long shift and j jas two short
shifts during this period.

To make it graphically, I would like to measure the following distance
(I hope that works properly):

Time t ------------------------------------> T
i at work        <---------->
j at work    <------->
I want:          <--->

My data now looks like this (only a minor part):

| worker                login               logout   spell |
|----------------------------------------------------------|
1. |      1   16jan2008 13:55:35   16jan2008 22:34:13       1 |
2. |      1   20dec2007 14:26:54   20dec2007 23:00:14       2 |
3. |      1   03may2008 07:49:56   03may2008 11:10:25       3 |

57. |      2   02jan2008 17:00:08   02jan2008 23:06:53       1 |
58. |      2   01dec2007 13:32:37   01dec2007 19:33:34       2 |
59. |      2   09jan2008 17:02:59   09jan2008 23:04:12       3 |

178. |      3   09may2008 08:00:12   09may2008 14:00:36       1 |
179. |      3   06nov2007 14:30:45   06nov2007 19:29:57       2 |
180. |      3   09oct2007 13:31:02   09oct2007 19:30:11       3 |

[...]

This example now is just for two persons. I think, when having a
solution for worker i and j, it can be easily extended to N workers by
looping.

I hope that it is clear what I mean. It would be really nice if
somebody could help me!!

Best regards,

Jan

--
Jan Sauermann (<j.sauermann@roa.unimaas.nl>)
Research Centre for Education and the Labour Market (ROA) / Maastricht
University

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