Summer Holidays and Seasonal Travel Activities in Attica: a Panel-based Comparative Approach
E Avramidou, P Papaioannou, A Deloukas, ATTIKO METRO S.A., GR
The seasonal mobility variation in Attica is investigated on the base of panel data.
A large household travel survey, conducted during two consecutive seasons in Attica for the needs of the Metro Development Study (MDS), confronted complex design and execution issues. The paper discusses the variation of travel characteristics drawn from a panel containing same households and the same type of information across periods.
The study area covers 79 municipalities in the Greater Athens Area (GAA: 94% of Attica population during the typical period) and 38 in the Rest of Attica Region (RAR: 6% of the said population). Section 2 of the paper discusses the design of the panel survey. Wave 1 covered the typical (spring) and wave 2 the summer period (July-September). In wave 2, a subsample of wave 1 households (hh) has been re-interviewed. The same questionnaire (with small modifications for the household and person data parts) has been used over both periods. The trip diary recorded weekday trips only. In such a controlled experiment design, person-specific characteristics remain essentially the same, and the temporal variation refers to certain contextual parameters and travel characteristics. Contextual parameters pertain mainly to climatic conditions, school holidays and use of available second homes. The sampling rate amount to 2% of the Attica population in the typical period (27?696 hh), large enough to get reliable population estimates. In the summer wave the rate was 0,5% in the GAA (i.e. every 4th of the hh sampled in wave 1) and 2% in the RAR. Publicity actions have given rise to a higher response rate in both periods and a lower attrition rate of the summer wave. Regarding the hh that participated in wave 1, the response rate in wave 2 amounts to 68% (rest: dropouts 12%, non-contacts 20%).
In section 3, the seasonal variation of certain travel characteristics is examined at an aggregate level. The summer population reduces in GAA by 16% and increases in RAR by 58%. Most of the households residing in the GAA retain the same residence over both periods. In the hot summer period though, numerous households migrate as a whole or as a part to a summerhouse in the RAR. Indeed, almost 150?000 persons are seasonally living during the weekdays at a summerhouse in RAR. The wave 2 hh size reduces by 3,4% in GAA and increases by 4% in RAR. From wave 1 information comes out that almost 10% of the hh population owns a summerhouse in RAR. However, linking information of both waves, only 1/3 of such residences are occupied during the summer weekdays. Referring to travel characteristics, the summer trip rate in GAA remains virtually stable, while in RAR increases by 4% as compared to the typical period figures respectively. The seasonal mobility level increases slightly as a whole. Comparing trip purposes by season, travel to work remains fairly stable, education drops dramatically due to school vacations and leisure trips increase from almost 14% to 23% in GAA and 36% in RAR respectively. The hot Greek summer favours car use to the expense of pedestrian and transit modes. Car occupancy increases from 1,30 to 1,38 during the summer period, an indication of larger party sizes engaged in leisure activities.
From the 5.921 hh participating in both waves, a subsample of 2.349 hh with full information is well-identified and considered for further investigation. Section 4 analyses the said subsample participating in both waves and living in GAA. Referring to mobile persons, the daily trip rate increases by almost 1% during the summer period and the daily trip duration by 4%. A comparative analysis of trips by origin and destination along periods reveals a weak increase of trips from central Athens as well as to RAR by more than 1% respectively, indicating an increased use of available summerhouses in RAR during the weekdays. A more focused elaboration pertains to the population living in GAA and owning a second home in RAR.
The findings concerning the seasonal variation within Attica are of importance for rapid growth areas in the Rest of Attica Region as demonstrated in the MDS projections.
Association for European Transport