Codes and Frequencies
MAIN reports the respondent's main activity during a given episode in the time diary.
MAIN codes activities into one of 69 harmonized activity categories. For example, a code of "33" in MAIN means the diarist performed voluntary work or a civic activity in that time slot.
Where main activity is missing but a valid secondary activity is recorded, the main activity is recorded as the secondary activity (see SEC), and the secondary activity is coded as no reported second activity. These are cases where the diarist has reported one valid activity.
If an activity cannot be coded, MAIN is assigned a value of 69.
Users should note how travel and personal care are handled in certain instances.
When main activity is missing but the diarist has recorded a mode of transport during this time period, we recode the missing main activity slot as unspecified travel (MAIN=62). Diarists may not record any travel when their travel episodes are very short, but may record a pattern in the diary that lets us know that they did travel and where in the day the travel took place.
Some surveys collected activities in half-hour time slots. Such long observation periods will include multiple episodes on occasion. In particular, short travel episodes can be left out of the half hour slots. In the case of missing short travel in these 30-minute time slot surveys, as well as in cases where the diarist coded one activity as the main activity and travel as the secondary activity, 20 minutes of the 30 minute slot is coded as the main activity, and 10 minutes as travel. The placement of the 10 minutes of travel depends on the sequence in which the time slot occurs. If a diarist has been working at the office for 7 hours, then has a time slot with missing or secondary travel where the main activity is recorded as paid work, then in the next episode is doing activities at home, the first 20 minutes of the episode that includes travel and the last 10 minutes is coded as secondary travel. In contrast, if after seven hours of paid work, the diarist then records an episode of eating at a restaurant with secondary travel, and the next time slot is a continuation of eating out, then the first ten minutes of the time slot with the short travel episode imbedded is coded as travel and the second 20 minutes is coded as eating out in the restaurant.
Diarists may not record any personal care when their episodes of personal care are short. In such diaries, you will find patterns of continuous reports of activity, and transitions where personal care is highly likely to have occurred (sleep for 2+ hours at home followed by other activities with no care, eating meals at home where the meal consumption lasts at least 10 minutes followed by other activities with no record of personal care). If such patterns are present, we make a flag variable for unreported personal care (0=no, 1=yes). If the diary is missing two basic activities, and one of these missing activities is personal care and we can flag this diary as having unreported personal care patterns, then we count this diary as a good diary. We do not alter the diary record in such cases, and users of the MTUS would have to make their own adjustments to the entries made by the diarists if they wish to account for such personal care.
Comparability — Index
MAIN is comparable across all samples.
- All activities.
- Austria: 1992, 2008
- Bulgaria: 2001
- Canada: 2005, 2010, 2015
- France: 1985, 2009
- Hungary: 1999, 2009
- Israel: 1991
- Italy: 2002, 2008
- Netherlands: 1975, 1980, 1985, 1990, 1995, 2000, 2005
- South Korea: 2004, 2009
- Spain: 2002, 2009
- United Kingdom: 1974, 1983, 1987, 1995, 2000, 2005, 2014
- United States: 1965, 1975, 1985, 1993, 1995, 1998, 2003-2019