Porto Tours publishes numbers, and a number is only as good as the place it came from. These are the rules the site works to, written down so a reader can hold it to them.
Where a figure comes from
A figure is taken from the party that sets it, wherever that party publishes it: the transport operator for its own fares, the city council for the tourist tax, the national statistics institute for income and population, the meteorological institute for climate normals, the European Union's own statistics for comparisons between countries. Prices from booking partners are their published catalogue prices, shown as "from" prices with the month they were read. A page that cannot support a figure with a source leaves the figure out.
Every research page names its sources at the foot, and publishes the data behind each chart as a file anyone can download and check. Where a number is an estimate or a projection, the page says so and shows the method.
Who writes and who checks
Research is written by Tiago Santos and reviewed before publication by Mariana Gomes, the editor-in-chief. Both are named on the page they worked on, with the date it was published and the date it was last checked.
Pages are re-checked on a schedule and after any change a reader would notice: a fare rise, a new tax rule, a fresh statistical release. The date at the top of a page is the date its figures were last verified, not the date the page was created.
Corrections
A mistake is corrected on the page itself, with the date of the correction, rather than quietly overwritten. Write to [email protected] with the page and the figure in question and it will be checked against the source.
Money
The site earns commission when a reader books through certain partners, which is disclosed near the top of every page that carries such a link and explained in full on the affiliate disclosure page. No partner pays for a mention, a rating or a place in a ranking, and the research pages carry no offers at all. A tour below the quality floor is never recommended, whoever sells it.