Titanic, Shrek and Paris: The Answers Everyone Gives First

Ask a room to name a ship, a disaster, a film from the 1990s or something lying at the bottom of the sea, and one word comes back every time: Titanic. Our analysis of Krillion's prompt banks puts a number on it. Titanic is Plankton, the bottom tier for answers the crowd gives most, on 22 different prompts, more than any other answer. Apple follows on 19, Shrek on 18 and Paris on 17.

These answers arrive first for three reasons. They are the most typical member of their category, they are the easiest thing in memory to reach, and they fit an unusual number of questions at once. In Krillion, where the score goes to the rarest correct answer you can find, that reflex is the most expensive habit you have. Below is the list, what drives each kind of default, and a checklist for catching your own.

These are the answers that sit in the Plankton tier on the most different prompts across roughly 2,500 live prompts:

• Titanic: 22 prompts
• Apple: 19 prompts
• Shrek: 18 prompts
• Paris: 17 prompts
• Cat, Batman, Fish, House, Water: 16 each
• London, Dog, Jaws: 15 each
• Los Angeles, Piano, Michael Jackson: 14 each
• Star Wars, Tokyo, Sonic the Hedgehog, New York City, Bee, Airplane, Jurassic Park, Car, Moon, Harry Potter: 13 each

Read down it and it falls into three families. There are the blockbusters (Titanic, Shrek, Jaws, Star Wars, Jurassic Park, Harry Potter, Batman), the world cities (Paris, London, Tokyo, Los Angeles, New York City), and the plain nouns a child learns in the first picture books (cat, dog, fish, house, water, car, moon, bee). Each family gets to the top of your mind by a slightly different road.

It is worth setting that against the size of the banks. A Krillion prompt accepts 137 distinct answers on average, and only 5.3% of all accepted answers are Plankton, while 14.7% are One in a Krillion. The water is mostly rare answers. The crowd just keeps piling onto the same few.

The first road is typicality. In the early 1970s the psychologist Eleanor Rosch, working at Berkeley, showed that a category is not a list of equal members. Some members are more central than others, and her work became known as prototype theory. In a 1975 study she asked 200 American college students to rate how good an example of furniture each item on a long list was, on a scale of 1 to 7. Chair and sofa came out on top. Lamp ranked 31st. Telephone ranked 60th.

Rosch also found that the typical members are recognised faster and come up more often when people simply list the members of a category. That is the mechanism behind "name a pet" producing cat and dog, "name a fruit" producing apple, and "name an instrument" producing piano. Nobody is guessing what other people will say. They are reporting the centre of the category, and everyone's centre is in nearly the same place because everyone learned the category from the same examples.

The second road is availability. In a 1973 paper in Cognitive Psychology, Amos Tversky and Daniel Kahneman described how people judge how common something is by how easily examples come to mind. A timed word game runs that the other way: whatever comes to mind most easily becomes the answer you type, and ease of recall is built by repetition.

That explains the people and characters on the list. Michael Jackson made Thriller, usually cited as the best selling album of all time. Sonic the Hedgehog has been Sega's mascot since 1991 and sits on lunchboxes, cereal boxes and film posters. Paris and London are the backdrop to a large share of everything ever filmed. On a 25-second clock you rarely get past your first two or three retrievals, and because a whole generation was fed the same films, songs and news, those first retrievals are shared.

The third family are the superlatives. Titanic (1997) was the highest grossing film in the world for twelve years until Avatar passed it, and it won 11 Academy Awards, tying the record set by Ben-Hur. Jaws (1975) is often called the first summer blockbuster. Shrek won the first ever Academy Award for Best Animated Feature. When a prompt asks for a film, the mind reaches for the one that was an event, the film everyone saw in the same year.

Cities work the same way. The capital, the largest city or the most visited one stands in for the whole country. A prompt like "Name a city in Japan" accepts 349 answers in our banks, yet most people's search starts and ends at the one city they have seen on screen most. The biggest, the first, the most famous: superlatives are where every mind looks first, which is exactly why they are crowded.

Typicality and availability explain why an answer comes first for one prompt. They do not explain why Titanic is Plankton on 22. For that, count how many category labels the one memory carries. Titanic is a ship, a shipwreck, a disaster, a film, a James Cameron film, a Leonardo DiCaprio role, a 1990s film, an Oscar winner and a famous thing on the seabed. Every one of those is a separate prompt, and Titanic is near the centre of all of them.

Apple is a fruit, a tree, a brand, a tech company, something red and a pie filling. Batman is a superhero, a film, a comic book character and a man in a cape. Water and the moon are so basic they fit dozens of loose prompts about things that are round, cold, in the sky or in a glass. Call these hub answers: one memory wired to many labels, so it fires whichever label the prompt pulls on. There is even a joke in the game itself. The Titanic wreck lies at about 3,800 metres in Krillion's ocean, so the answer everyone gives is also a place every good dive sinks past.

Before you press Enter, run your answer past these seven questions. A yes to any one of them means the crowd probably got there first.

1. Would it be the picture in a children's book? If a first reader would illustrate the category with it, it is the prototype.
2. Is it the biggest of its kind? Highest grossing, best selling, tallest, most visited, the capital. Superlatives are the first place everyone looks.
3. Would it answer five other prompts? If the same word also fits "name a disaster" and "name a 90s film", it is a hub, and hubs are crowded.
4. Did it arrive in under a second? Speed of recall is availability you can feel. The faster it came to you, the more people it came to.
5. Is it the category's own name in disguise? "Fish" for something that lives in water, "car" for something with wheels. If the answer nearly restates the question, half the room typed it.
6. Did everyone meet it at the same moment? A summer blockbuster, a number one record, a book set at school. Shared events make shared memories.
7. Would you have said it ten years ago? Defaults are stable. If your answer to this prompt has not moved in a decade, nobody else's has either.

The checklist is for noticing, not for choosing what to say instead; our guide to getting better at Krillion covers that. A useful experiment is to spend one dive in Krillion Unlimited typing your very first thought on every prompt, then watch the tiers. Most players are surprised how many of their instincts are Plankton, and once you have seen it you start to feel the reflex arrive.

Yes, when the game asks for it. Family Feud style surveys pay for reading the crowd, and our sister game Noillirk turns Krillion upside down: the more common your answer, the higher your krill's balloons climb, and the survey's single top answer scores Sky High. Every reflex on the checklist is a strength there. The skill is the same in both directions: knowing where the centre of the category sits, so you can aim straight at it or deliberately away.

The next time a prompt comes up, give yourself the count-in to notice what arrives first. If it is a blockbuster, a capital or a word from a picture book, let it go and keep looking. The Krillion game is free, runs in your browser with no sign-up, and has no daily cap, so you can test the checklist on as many dives as you like and find out how far down the rare answers really are.

Rosch, E., Cognitive Representations of Semantic Categories (Journal of Experimental Psychology: General, 1975).

Tversky, A. and Kahneman, D., Availability: A Heuristic for Judging Frequency and Probability (Cognitive Psychology, 1973).

Wikipedia, Prototype theory.