Letter: Reconviction: scientific methodology vs empirical experience
Your support helps us to tell the story
From reproductive rights to climate change to Big Tech, The Independent is on the ground when the story is developing. Whether it's investigating the financials of Elon Musk's pro-Trump PAC or producing our latest documentary, 'The A Word', which shines a light on the American women fighting for reproductive rights, we know how important it is to parse out the facts from the messaging.
At such a critical moment in US history, we need reporters on the ground. Your donation allows us to keep sending journalists to speak to both sides of the story.
The Independent is trusted by Americans across the entire political spectrum. And unlike many other quality news outlets, we choose not to lock Americans out of our reporting and analysis with paywalls. We believe quality journalism should be available to everyone, paid for by those who can afford it.
Your support makes all the difference.From Mr Len Salem
Sir: The only valid test for the usefulness of Professor Copas's formula is this: take, say, 100 case histories not included in the original survey sample and apply his method to predict the likelihood of re-offending. Give the same case histories to a selection of experienced probationers and ask them to do the same. Compare the predictions with what, in fact, happened and you will know which is the more reliable guide. It may well be that this elementary test has already been performed; if not, it should have been.
Yours sincerely,
Len Salem
London, W5
Join our commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies
Comments