Behavioral economics theory explains a popular banana-clicking video game

In the ever-evolving online gaming landscape, one seemingly simple online game has captivated players. The free-to-play clicker Banana has amassed more than 850,000 concurrent players on the gaming platform Steam.

The game involves clicking on bananas and being rewarded every so often with "skins." These are essentially virtual items that can be sold on the Steam marketplace for real money.

While most banana skins are close to worthless, some rare ones may sell for much more (much like rare NFTs did at one point). The highest-recorded sales have raked in upwards of US $1,300 (about A $1,950).

Since its release on April 23, Banana has eclipsed major titles such as Baldur's Gate 3 and Apex Legends, seemingly demonstrating mass appeal and the creation of a bustling virtual economy.

At the same time, most of the "players" aren't real people, according to the developers. They are bots, deployed in masses to maximize earnings for their creators.

Some might consider Banana a new and counterintuitive phenomenon. But it actually ties into a probability puzzle that's more than 300 years old.

This game highlights ongoing debates in behavioral economics about how people value future prospects and manage uncertainty—especially as these prospects come from increasingly complex and automated economic systems.

A game promising infinite amounts of money?

The renowned St. Petersburg paradox is likely the earliest known behavioral dilemma and is thought to have catalyzed the development of "decision theory" as a scientific field.

The paradox was formulated by Nicolas Bernoulli in 1713 and later popularized by his cousin Daniel Bernoulli during his time in St. Petersburg, Russia.

It revolves around a theoretical coin game in which a player makes an initial offer (of their choosing) to play. Let's imagine the game pool begins at a value of $2. The coin is repeatedly flipped and every time it lands on heads, the potential winnings double. But when it lands on tails, the player must leave with whatever sum is in the pool.

As such, the player has a ½ chance of winning $2 dollars, a ¼ chance of winning $4 dollars, and a 1/8 chance of winning $8 dollars, and so on. And as long as the coin theoretically keeps landing on heads, they could end up winning an infinite amount of money.

The "paradox" here is that despite the infinite theoretical winnings, practical offers to play the game for any amount higher than $2 are likely to remain low. And this highlights a fundamental inconsistency between expected values in theory and real world decision-making.