1. Improving the Accuracy of Outbound Tourism Statistics with Mobile Positioning Data
Ossi Nurmi
15th Global Forum on Tourism Statistics, Cusco, Peru
November 2018

2. Introduction What is it?
Outbound tourism means visits by the residents of a country to another country
Why is it important?
Accurate outbound tourism statistics are important for international trade in services and balance of payments statistics
So what’s the matter?
Outbound tourism data are typically collected by surveys, typically CATI or CAWI
Alternative or complementary data sources are needed because survey small sample sizes are small and survey response rates are declining
What about mobile positioning then?
Mobile network operators (MNOs) store ’traces’ of the mobility of people
In outbound tourism, these traces are roaming events (calls, sms, data) of mobile devices used in a foreign country
They can be translated into outbound trips from a country to all other countries

3. Data process
OPERATOR 1 S T A I C F N L D
PROCESSED RAW DATA
SUBSCIBER ID
TRIP ID
TRIP DURATION
MONTH
COUNTRY CODE
AGGREGATE DATA
YEAR
MONTH
COUNTRY
TYPE OF TRIP
DURATION
NUMBER OF TRIPS
RAW DATA
SUBSCRIBER ID
COUNTRY CODE
EVENT TIME
OPERATOR 2
RAW DATA
PROCESSED RAW DATA
AGGREGATE DATA
The data process was established by Statistics Finland during 2016 – 2018 as part of Eurostat’s ESSNet Big Data Project
Only MNOs are allowed to process their data using automatic means in the current legislation

4. Mobile roaming events and trips
Roaming events = calls, sms or data in a mobile network abroad
First event indicates beginning of trip to a country
The end of trip is determined based on time gaps and following events
In this example, 5 outbound trips identified during the 30 day period
2 day trips
2 short trips (1-3 nights)
1 long trip (over 3 nights)

5. Top down approach for data validation
Finnish Travel –survey
Mobile Positioning Data
Sample size
28,500 persons
< 70% of population
Outbound trips observed
< 3,000 per year
< 7 million per year
Average weight of one outbound trip
< 4,000
< 1.3
Total number of outbound trips in 2017
10.5 million

6. Top down validation: number of trips
Estonia and Sweden nearly half of all outbound tourism
MNO data provides
24% less trips to Estonia
44% more trips to Sweden
Some countries are exaggerated and others underestimated
Conclusion: Number of trips in the MNO data is biased depending on country
Possible reasons include:
Non-tourism trips
Border noise
Phones switched off or not used
Sample bias (one MNO missing)

7. Top down validation: monthly seasonality
Conclusion: monthly survey estimates are affected by randomness. MNO data provides a more accurate monthly seasonality.

8. Strengths and weaknesses
Finnish Travel -survey
Mobile positioning data
Strengths
Scope is clean: only tourism trips are included
Provides supporting information of the trip (ie. purpose of trip, expenditure, means of transport and accommodation)
Granularity: millions of trips covering nearly all destination countries
Monthly seasonality of tourism is more accurate
Weaknesses
Granularity: very few observations per year, covering only a few destination countries
Monthly seasonality estimates are affected by randomness
Scope is not clean, there are many sources of over- or underestimation
No supporting information of the trip

9. Proposed method for improving survey data
Use the total number of annual outbound trips from the (Finnish Travel) survey as the frame
Determine the (95%) confidence intervals for each destination country
Select the more reliable source data (survey or MNO data) for outbound trips separately for each destination country.
Calculate a coefficient factor for trips to those countries that will be based on MNO data
Apply the monthly seasonality trend based on MNO data separately for each country

10. Confidence intervals for number of trips

11. 2017 results by country
Top 10 countries
Small countries
(top )

12. Summary of 2017 results Estimated based on survey data
Estimated based on MNO data
Total
Number of trips by country
9.0 million
1.5 million
10.5 million
Number of destination countries 24
129
153
Average trips per country
380,000
12,000
69,000

13. Thank you
Ossi Nurmi
15th Global Forum on Tourism Statistics, Cusco, Peru
November 2018
26 February 2019
Ossi Nurmi