There is another article linked from this one, that contains a slightly more detailed description of the game:
> Participants clicked on two planets to amass points which put them in the running to win a monetary prize.
Unbeknown to the participants, clicking either planet led to a similar amount of reward, but could also result in the emergence of different spaceships.
From the player's POV, the main task of the game wasn't about the spaceships, it was about finding the planet with the most reward (as the players didn't know the rewards were mostly equal).
I wonder if the "compulsive" behavior might have something to do with the player believing that the planet with the pirate ship were also the one with the largest trade reward - so in their mind, abandoning the planet completely would be a bad strategy, because they might lose more points by not trading with the planet than keep by not triggering the spaceship.
Especially if the spaceship only appears in 20% of all clicks and the player can make themself believe it will appear "almost never anyway".
> Participants clicked on two planets to amass points which put them in the running to win a monetary prize.
Unbeknown to the participants, clicking either planet led to a similar amount of reward, but could also result in the emergence of different spaceships.
From the player's POV, the main task of the game wasn't about the spaceships, it was about finding the planet with the most reward (as the players didn't know the rewards were mostly equal).
I wonder if the "compulsive" behavior might have something to do with the player believing that the planet with the pirate ship were also the one with the largest trade reward - so in their mind, abandoning the planet completely would be a bad strategy, because they might lose more points by not trading with the planet than keep by not triggering the spaceship.
Especially if the spaceship only appears in 20% of all clicks and the player can make themself believe it will appear "almost never anyway".