A hard IQ test that gets harder as you go

A hard IQ question is not one with obscure words or a trick. It is one where you have to find and hold several rules at once. Researchers who study matrix puzzles have found that the number of rules in an item, and how unusual those rules are, predict how many people get it wrong.

Patricia Carpenter, Marcel Just and Peter Shell studied how people solve Raven-style matrices in 1990. The people who scored highest were not faster at seeing shapes. They were better at keeping several half-solved rules in mind and at breaking a problem into parts. That is the skill a hard item tests.

So difficulty on this test comes from four things:

• More rules per item. Easy items change one thing. Hard items change shape, colour, count and position at the same time, each on its own rule.
• Rules that skip. Some patterns alternate, or change only on every second step, so the obvious next step is wrong.
• Rules that hide. A feature that never changes can look like part of the pattern. Knowing what to ignore is half the work.
• Time. Twelve minutes for 25 items is under 30 seconds each. A hard item that would fall in two minutes may not fall in thirty seconds.

What it does not use: vocabulary, general knowledge, school maths or riddles that depend on reading the question a certain way. Those make a test harder for some people for reasons that have little to do with reasoning.

These are practice items written for this page, not questions from the test. Each one is at the hard end. Try to name every rule before you pick an answer.

If you got all three, the hardest items in the full test will feel familiar but faster. If you got none, that is normal on a first try: hard items are hard mostly because the method is unfamiliar, and the method is learnable. The IQ test questions and answers page walks through ten more, step by step.

People who do well on hard items tend to work the same way. You can copy the method.

1. List the features. Shape, colour, count, size, shading, rotation, position. Say them to yourself.
2. Test one feature at a time. Does the colour change across the row? Down the column? Not at all? Settle one feature before you move on.
3. Check rows and columns. A rule that works across rows but breaks down a column is usually the wrong rule.
4. Predict before you look. Describe the missing cell in words, then find it among the options. Scanning the options first lets a near miss pull you in.
5. Eliminate. If you cannot finish, rule out every option that breaks a rule you are sure of. Two sure rules often leave one option.
6. Move on. With under 30 seconds an item, one stubborn question costs you two easier ones later. You can come back while the timer runs.

This is also why practice helps a little on a retest. People who have seen matrix items before often score somewhat higher the second time, mostly because the method is no longer new. It is one reason a first attempt is the most honest one.

Difficulty depends on the item mix, the time limit and the ceiling: the highest score a test can give with any precision. This table compares the LifeScore test with well-known tests people call hard.

Two things stand out. Professional tests are much longer, which is what lets them measure precisely near the top. And a short test that claims to measure 160 or 180 precisely is claiming more than its length allows. See the Raven's guide and the Mensa practice test for more on those two.

On the standard scale, where the average is 100 and the standard deviation is 15, high scores become rare quickly. These figures are computed from the normal curve.

Every score also has error around it. A test with a reliability of 0.90 has a standard error of about 4.7 IQ points, so a 130 really means "somewhere around 125 to 135". A shorter, less reliable test widens that band. Treat a single high score as a strong hint, not a fact. Each score has its own page, such as what an IQ of 130 means and what 140 means.