[Slot Machine Design] is a profound subject. Designing a fun and attractive slot machine is an eternal topic for every slot machine designer or probability engineer, and currently, no one can clearly point out what kind of design will definitely be fun.
However, I think all designers would agree that generally speaking, if RTP is taken out as one of the factors, games with lower RTP usually have a harder time attracting players, whereas games with higher RTP tend to attract players more easily.
Does a high RTP really attract players?
However, if we extremely design a slot machine with a very, very high RTP, even far exceeding 100, such as an RTP = 10,000 slot machine, would it really attract players to continuously play crazily?
To answer the above question, it is necessary to understand what the [St. Petersburg Paradox] is.
First, here is an introduction from Wikipedia:
The St. Petersburg Paradox is a paradox in decision theory, proposed by Nicolas I Bernoulli. In 1738, Daniel Bernoulli used utility theory to answer this problem, thus forming the expected utility theory.
In the 1730s, mathematician Daniel Bernoulli, cousin of Nicolas I Bernoulli, posed a question in a letter to French mathematician Pierre-Simon de Laplace: Flip a coin, if it lands heads on the first flip, you earn 1 dollar. If it lands tails on the first flip, then you must flip again, if the second flip is heads, you earn 2 dollars. If the second flip is tails, then you must flip a third time, if the third flip is heads, you earn 2*2 dollars... and so on, the game might end after one flip, or it might go on indefinitely.
The question is, how much money would you be willing to pay to participate in this game? The amount you are willing to pay should equal the expected value of the game:
The expected value of this game is infinite, meaning you would be willing to pay an infinite amount of money to participate in this game. However, you are more likely to earn just 1 dollar, or 2 dollars, or 4 dollars, etc., and not an infinite amount of money. So why would you be willing to pay an infinite amount of money to participate in the game?
In his 1738 paper, Daniel Bernoulli offered a solution to this paradox, using the concept of utility, to challenge the decision-making criterion of monetary expected value. The paper mainly includes two principles:
1. The principle of diminishing marginal utility: A person prefers more wealth to less, i.e., the first derivative of the utility function is greater than zero; as wealth increases, the rate of satisfaction increases at a decreasing rate, the second derivative of the utility function is less than zero.
2. The principle of maximum utility: Under conditions of risk and uncertainty, an individual's decision-making behavior is guided by the criterion of achieving the maximum expected utility value rather than the maximum expected monetary value.
Returning to the game mentioned in the introduction, if the participation fee is 100,000 dollars, I think very few people would be willing to play. Applying the concept of the paradoxical game to the design of slot machines, that is, designing a slot machine that assumes each spin costs 100,000 dollars, this slot machine has a
1/2 chance of winning 1 dollar, 1/4 chance of winning 2 dollars, 1/8 chance of winning 4 dollars... 1/2K chance of winning 2K-1 dollars
K = 20 million is enough, no need to be infinite. Then the expected value of each spin is winning 10 million dollars, which is just what was mentioned at the beginning of the article, an RTP = 10,000 slot machine.
If it were you, would you be willing to spend 100,000 dollars on each spin?
So why does a slot machine with an RTP as high as 10,000 not attract players?
The answer from Wikipedia, that is, an individual's decision-making behavior is guided by the criterion of achieving the maximum expected utility value rather than the maximum expected monetary value.
In gambling industry terms, what players pursue is the feeling of having a chance to win big, usually the experience brought by triggering free games, rather than pursuing a gambling game with the highest RTP.
Going deeper into Volatility, an attractive slot machine must have an appropriate Volatility model, neither high nor low.
So what exactly is the appropriate Volatility model? As mentioned at the beginning of the article, no one has yet been able to clearly point it out.
This question also does not have a fixed best solution, as player preferences vary across different markets and platforms, and even within the same market and platform, player tastes may gradually change over time, so this is truly an eternal topic for every slot machine designer or probability engineer.
