How to Make Accurate Predictions

And why experience doesn’t help much.

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Julie is a senior in university. By the time that she was four years old, she was already a fluent reader. What is her grade point average (GPA)?

When broken down, these are fundamentally two questions:

1. Start with an estimate of average GPA.

2. Determine the GPA that matches your impression of the evidence.

3. Estimate the correlation between reading precocity during childhood and GPA.

4. If the correlation is .30, move 30% of the distance from the average to the matching GPA.

The first step ascertains the baseline, which is the GPA that we would have predicted if we knew nothing else about Julie other than she was a senior at college.

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Productivity, craftsmanship, and the pursuit of excellence at work. Writing now at jennifertchan.substack.com.

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