3.107. Household‑type surveys cover all the procedures for questioning residents, while present in their usual environment (usually in their home), about the trips they have taken, after the completion of such trips, during a specific reference period, e.g., the past month. The recommended methodology entails a household survey which may be a stand‑alone survey designed specifically, and only to collect tourism data or a module included in a wider, already existing survey, such as a household income and expenditure survey (HI/ES) (IRTS 2008, paras. 3.41 and 4.31) while surveys can be conducted for this purpose on the basis of the selection of households, as is most frequently the case, some countries, such as Austria, select individuals directly from a general database of residents and conduct the interview by telephone (using the CATI method). It must be underlined that surveying households is used in this context only as a means of selecting resident individuals; the household as such is usually not an observation unit but only a selection unit (for an exception in this regard, see Box III.31).
3.108. Such surveys are conducted through face‑to‑face interviews or by telephone. Countries that had achieved high penetration of landline telephones in households found that telephone surveys considerably reduced cost by eliminating the need for interviewers to be sent around the country. However, in recent years, the rapid growth of mobile (cell) phones and the associated lower penetration of landlines in households are generating concerns regarding the representativeness of such a methodology. If interviewing is conducted only via landlines and does not include mobile phones, there could be a significant bias in the sample, e.g., an underrepresentation of younger people who have a higher propensity to use only a mobile phone.
3.109. As mentioned in section B.2 above, the frequency of household‑type surveys is basically dependent on cost; however, other factors, relating to the characteristics of resident visitors and their tourism trips, should also be considered when the frequency of observation is being determined.
3.110. Countries may try to establish the characteristics of trips and of persons taking trips independently of,or with frequencies that differ from that used in, the measurement of associated expenditures. Domestic tourism flows should be measured with high frequency (monthly or even more frequently in specific periods such as high season), since their characteristics tend to fluctuate significantly throughout the year (exhibiting seasonality) and, although to a lesser extent, from year to year (see paras. 3.18–3.19). The average expenditure per person or per person per day associated with each characteristic of a tourism trip, on the other hand, tends to be less volatile. Hence, it can be observed less frequently (e.g., every three to five years) and measured through extrapolation using relevant price indices once the volume and characteristics of the trips are clearly established. The advantage of this approach is that it reduces the need for collection of good‑quality expenditure data, which is difficult and can add considerable cost to the survey when included.
3.111. Apart from other particularities (see sect. D.2), the following issues arise in the use of household surveys for purposes of tourism:
- As all trips have a specific duration, with beginning and final dates, it is necessary to determine the trips that should be taken into consideration in the count and the durations to be reported. As was explained in paragraph 3.68 above, the period of reference of the observation and the period of occurrence of a trip might not coincide. Because individuals can report only on trips that were completed, the universe of domestic or outbound trips to be reported refers to trips that ended in the period of reference, irrespective of their date of initiation. Pursuant to this criterion, all trips will be reported (only once), and their reported duration should be the actual duration of absence from the usual environment, irrespective of the date of commencement of the trip. This means that the actual duration of a reported trip might be longer than the period of reference.
- The number and characteristics of domestic trips taken during the period of reference need to be ascertained for each person interviewed, and a distinction needs to be made between tourism and non‑tourism trips. The information provided may be used to set up the universe of trips.
- Complete information can be collected only on trips completed during the period of reference (irrespective of their starting date), which needs to be clearly stated when the interviews are conducted. These characteristics will then be extrapolated statistically to the whole universe of trips, taking into consideration the fact that in a reference period, some individuals might complete more than one trip.
- The characteristics that need to be observed relate to the frequency of similar types of trip, the duration of the observed trip, its purpose and the distance travelled. Questions should be formulated so as to permit easy identification of the cases described below. If possible, respondents should not themselves be allowed to identify which trips are tourism trips, since the general public tends to equate them with recreational travel. Only round trips in which travellers leave their usual environment (see chap. II, sect. B.2 above, and IRTS 2008 chap. 2, sect. B.4) should be considered tourism trips. The following should not be considered tourism trips:
- Trips between the place of residence of the respondent and his or her place of work or study.
- Frequent trips (at least one per week) for, inter alia, shopping, family visits, religious purposes, health and medical care, and education and training.
- Domestic trips entailing a stay at a destination of more than a year, which implies a change in place of residence.
- Domestic trips to a place in order to take on a non‑permanent, short‑term job for pay by an entity in the place visited (see IRTS 2008, paras. 2.35 to 2.38). If the job is permanent and the individual moves frequently and repeatedly between the place of work and the place of residence of the household, the trip is not to be considered a tourism trip either, since the individual is moving between two locations that are both part of his or her usual environment (see IRTS 2008, para. 2.25).
- Domestic trips, considered to be within a very short distance (either as measured in terms of the distance itself or because they do not involve the crossing of administrative borders) from the household’s main place of residence (treated as being within the usual environment, (see IRTS 2008, para. 2.52)).
- On the other hand, trips to vacation homes should be considered tourism trips (see para. 2.25 and IRTS 2008, para. 2.28). In countries where such trips are frequent, their detailed characteristics might call for a specific sub‑module in the survey questionnaire. This module on vacation homes might be relevant not only when trips to those homes are frequent, but also when they are used over a long period of time. For instance, consider the following case: a household moves for the whole summer season to a vacation home in the countryside which is located in a municipality close to the main one from which the parents travel to work every day while the children remain there with their grandparents. We might even be tempted to say that the vacation home becomes the main dwelling for that period. (However, we do not treat it as such in tourism statistics.) While many trips – tourism or otherwise – may be made while a person is staying at his or her vacation home, only one tourism trip should be recorded, i.e., the stay at the vacation home.
- For each trip identified as a tourism trip, it is necessary to determine whether the visitor travelled alone, or with other members of his or her household (if a whole household has been selected) – or members of other households – within a travel party.
- Depending on the expected number of trips to be reported for each household (that has taken at least one tourism trip during the period), the characteristics can be observed, for any of the following (see Box III.29):
- All trips taken by household members during the reference period (if short)
- All trips taken by one selected member of the household during the reference period (also if short).
- One trip taken by one selected household member during the reference period (usually the last trip, or one selected at random).
- Another combination of trip and household member (see Box III.29).
- In cases where a household (or the individual being interviewed) has taken more than one in‑scope trip during the reference period, some countries use the following methodology, they collect details of only one trip (usually the last one taken) but count the total number of trips taken. These data would then be used in the sample expansion process to estimate the total number of trips taken.
3.112. Besides the personal characteristics of the person taking the trip and, eventually, of the travel party, which are all characteristics attached to the trip, the following additional characteristics should be observed:
- Duration of the trip, in terms of overnights away from the usual environment. For trips entailing no overnights, the number of hours (classified in relevant groupings) might be of interest.
- Destination or place visited that was central to the decision to take the trip (see para. 2.84 above and IRTS 2008, para. 2.31).
- Places visited during the trip (necessarily a round trip), including the length of stay (overnights or hours) in each place and the type of accommodation chosen, if relevant. Each place can be defined as a region (if the country of reference is divided into regions), a city, a specific tourism destination or any other national subdivision identified for analytical purposes.
- Types of accommodation whose determination (see chap. II, sect. C.1.6 above, and IRTS 2008, paras. 3.35-3.38) should at a minimum separate market from non‑market accommodation and be consistent with the classifications used for the characterization of inbound tourism and the supply of accommodation services.
- Main mode of transport, defined as that used to travel the greatest distance (IRTS 2008, para. 3.32). Secondary modes of transport might also be identified (see chap. II, sect. C.1.5 above).
- Main purpose of the trip: its classification should be aligned to the international recommendation (see chap. II, sect. C.1.1, above, and IRTS 2008, paras. 3.10-3.20). Some countries might find it relevant to ask for the main purpose and secondary activities, for the trip as a whole or for each place visited information that may be pertinent for subnational tourism analysis. However, countries should be aware that, while the information collected on purpose and even on the multiple reasons for the different visits that make up a trip might be of interest it would be extremely burdensome to put the collection process into practice. Further there is a serious risk that the quality of the responses would be adversely affected.
3.113. Same‑day trips and trips to vacation homes should be identified separately and given special treatment within a specific sub‑module.
 The individuals are also collection units, as they might take more than one tourism trip during the reference period.