And here another set of my observations after few days off. In between I could participate on great conference ALE 2011 in Berlin - some insights come later.
- Ticket is bound to specific tour
Clever. This aspect decreases the variance and thus subjective value for visitors. On other side a lot of conflicts can be avoided this way (assignment to certain tour takes place already when buying ticket)
- The number of tourists in one batch/tour is limited
Simple rule to decrease variance and thus increase predictability. Whole tour is then optimized to this number in one batch.
- You cannot buy ticket for a tour that is already sold out
Relevant to previous point - however it says that information about maximum and actual batch size is available already on ticket counter.
- In front of the tour entrance you can find people in three queues
- prepared as one batch (5 minutes to start)
- finishing the collection of the group for tour (10 minutes to start)
- just opened queue (15 minutes to start)
- the rest of visitors is waiting around until their tour is next to be collected in waiting queue
- Enter to the tour queue is automated based on the ticket (to minimize transaction costs)
- Last stage in the tour is without explicit guide - The guider is already on the way to next group that is in-between collected in the first room of the castle
- No tourist gadgets can be found in the entrance area - these are side artifacts that could influence the throughput
- During the tour you can hear small bell. I am not sure, but I suspect that this is a synchronization signal for all tours inside the castle. Every guider gets a feedback if his group is too slow or in opposite - should slow down. This keeps the process cadence stable during the whole day.
- Whole capacity is not used on 100% to keep the overall throughput on maximal level. (See Allen-Cunneen Approximation for queue length and resulting process performance as consequence of Little's Formula)
- And results?
- People are happy as service is excellent
- More than 1.3 million people visit annually, with up to 6,000 per day in the summer. This means up 10 hours every five minutes one batch with 25 people, with very small buffer for unpredictable events. Wow.