Which Has More Dots Game
Two flashes, two swarms. Pick the bigger one.
About Dot Compare
Dot Compare flashes two groups of dots next to each other, a blue one on the left and a yellow one on the right. After a second or less they disappear and you choose which side had more. There is no counting involved, only a feeling for which swarm was more crowded.
The ratio between the two groups shrinks as you go up. At level 1 one side has about 55 percent more dots, which is clear at a glance. At level 10 it has only about 9 percent more, a difference that is at the edge of what people can tell apart. Dot sizes vary within each group, so you cannot simply compare how much of the field is covered.
How to play
- Look at both fields at the same time, with your eyes at the middle of the screen between them.
- When they vanish, tap Left (blue) or Right (yellow), or press 1 or 2.
- If you are not sure, follow your first impression rather than a second guess.
- After your answer the note shows the exact counts, so you learn how large a 10 or 20 percent difference really is.
Two groups of dots flash up side by side for a moment. Choose the side with more dots. Dot sizes vary, so area is not a reliable clue.
How scoring works
A right answer scores 100 and a wrong one 0, and in endless mode a right answer counts as a passed round. The larger group has between 14 and about 100 dots, and its count is 1.55 times the smaller on level 1 and 1.09 times on level 10.
Each dot has a random size between 7 and 11 pixels, in both groups, so area and density are only a partial clue. The flash lasts 1.5 seconds on level 1 and 0.8 seconds on level 10, and then you have 8 seconds to answer. Which side is larger is decided by a coin flip.
What it trains
It is the textbook way of testing the approximate number system: comparing two numerosities too large to count. It trains quick visual estimation, which we use when we decide which queue is shorter or which pile is bigger.
It is also a good lesson in humility. The difference between 40 and 44 dots is invisible at first, but with practice and calm looking you will find yourself getting more of the close ones right.
Tips for a higher score
- Let your eyes rest in the middle of the screen so that you can see both groups with your peripheral vision, rather than moving back and forth.
- Do not rely on size. A group with larger dots looks heavier, but the question is about how many, not how much ink.
- Avoid counting a small part: the flash is too brief. Take the whole group in at once.
- When two sides look equal, your guess is as good as any, but it often pays to pick the side that looked more crowded in the first instant.
- Play a few rounds in a row. Quick rounds in sequence help build an intuition for ratios.
The idea behind it
The comparison of two dot arrays is a standard paradigm in numerical cognition research. The error follows Weber's law: the larger the numbers, the larger the difference needed for a reliable judgement, so what matters is the ratio, not the difference. Adults often reach a ratio of about 7 to 8, which corresponds to an acuity of roughly 0.14 on the Weber fraction scale.
Researchers control for non-numerical cues such as the total area of the dots, their density and the size of the cloud, because people can use these cues as a shortcut. Studies suggest that adults make use of both number and these other cues, which is why the game keeps sizes varied.
Frequently asked questions
Is it a coin flip when they look equal?
The two groups are never equal. The larger group always has at least a few more dots, so there is always a right answer.
Why are the dots different sizes?
Random sizes break the link between the covered area and the number, so you cannot pick the right side from the area alone.
Which game trains the same sense?
Dot Flash asks for an estimate of one swarm, and How Much More? asks for the difference between two groups.
Related games
Free, no account. Your best scores are saved on your device.