Speed Estimation Study

In this short exercise you will watch a video of a traffic incident, then answer one question about it. Your answer will be added to responses from other readers, and you will be shown the group results at the end.

There are no right or wrong answers — just give your honest impression.

Watch the clip

Watch carefully, then click Continue when you are ready.

Your estimate

km/h
Please enter a speed between 1 and 300 km/h.

Results

Your estimate:

Mean estimates by question wording

“How fast when it collided with the car?”
“How fast when it smashed into the car?”
Your estimate
0306090120 km/h

What does this show? This exercise is modelled on a classic experiment by @loftus1974 (Loftus & Palmer, 1974). They showed participants a film of a car accident and then asked either “About how fast were the cars going when they smashed into each other?” or “…when they hit each other?” (and three other verbs). Participants given the word smashed estimated significantly higher speeds than those given hit.

The verb does not change what was seen — it changes how the memory is subsequently encoded and reported. This is an example of post-event misinformation: language used after an event can alter a witness’s account of it, even when the witness is unaware that any influence has occurred.

Your response has been saved. The means above reflect all readers of this textbook who have completed this exercise.