What it is
The hard-easy effect is a prediction bias. It suggests that we are overconfident in our ability to complete difficult tasks, and under-confident in our ability to be successful in easy tasks.
Why it happens
There is a lot of debate as to why the hard-easy effect exists. Most theories rest on the premise that other biases lead to the effect. For example, memory recollection biases mean that there is room for error when we answer a question, but that we don’t adjust our confidence accordingly.
The disproportionate amount of information we know about easy versus difficult tasks may also be a cause of the hard-easy effect. For difficult questions, we have less knowledge about the topic, meaning that we are less likely to think of evidence that goes against our answer. When the question is easy, we may know more about the topic, and be able to come up with evidence that goes against our answer, making us less confident in it.
Example 1 – It doesn’t just occur for subsets
While most of the studies conducted to examine the hard-easy effect measure whether confidence is accurate in predicting success for individual questions or items, it has been found that the hard-easy effect is also seen for overall tasks. If an entire exam is easy, people are under-confident in how well they did, whilst they are overconfident in how well they did in a hard test.
Example 2 – Intelligence doesn’t negate the hard-easy effect
We may believe that the more intelligent we are, the more realistic we would be, making us better at predicting our success in different tasks. However, it seems as though intelligence, at least in terms of academic intelligence, has no impact on the hard-easy effect. Being intelligent is not enough to avoid the hard-easy effect.
How to avoid it
Whilst intelligence may not negate the hard-easy effect, some research has suggested that knowledgeability about a specific topic may help counter being overconfident in how well we performed on difficult tasks.