I see that some vocations in my O/D analysis are considered “Long Distance”, but all my journeys took place in the same county - how can this be?

Vocations reflect a vehicle's patterns across its full travel area over 3 months, not just the trips within a single county or a single analysis.

If their driving behaviors have changed, it will take some time for the vocation models to pick up on this and re-assign them. This could also occur if the trip chaining value used is not enough to string the trips together to show a pattern more indicative of long distance driving.