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Software 'No More Accurate Than Untrained Humans' At Predicting Recidivism (theguardian.com)
An anonymous reader quotes a report from The Guardian: The credibility of a computer program used for bail and sentencing decisions has been called into question after it was found to be no more accurate at predicting the risk of reoffending than people with no criminal justice experience provided with only the defendant's age, sex and criminal history. The algorithm, called Compas (Correctional Offender Management Profiling for Alternative Sanctions), is used throughout the U.S. to weigh up whether defendants awaiting trial or sentencing are at too much risk of reoffending to be released on bail. Since being developed in 1998, the tool is reported to have been used to assess more than one million defendants. But a new paper has cast doubt on whether the software's predictions are sufficiently accurate to justify its use in potentially life-changing decisions.
The academics used a database of more than 7,000 pretrial defendants from Broward County, Florida, which included individual demographic information, age, sex, criminal history and arrest record in the two year period following the Compas scoring. The online workers were given short descriptions that included a defendant's sex, age, and previous criminal history and asked whether they thought they would reoffend. Using far less information than Compas (seven variables versus 137), when the results were pooled the humans were accurate in 67% of cases, compared to the 65% accuracy of Compas. In a second analysis, the paper found that Compas's accuracy at predicting recidivism could also be matched using a simple calculation involving only an offender's age and the number of prior convictions.
The academics used a database of more than 7,000 pretrial defendants from Broward County, Florida, which included individual demographic information, age, sex, criminal history and arrest record in the two year period following the Compas scoring. The online workers were given short descriptions that included a defendant's sex, age, and previous criminal history and asked whether they thought they would reoffend. Using far less information than Compas (seven variables versus 137), when the results were pooled the humans were accurate in 67% of cases, compared to the 65% accuracy of Compas. In a second analysis, the paper found that Compas's accuracy at predicting recidivism could also be matched using a simple calculation involving only an offender's age and the number of prior convictions.
They said the software used 137 data points on determining the probability of re-offending but they were no better than if someone use just 2, age and prior convictions. Perhaps I've had more statistics training than most but this seems highly probable. This is pretty basic data analysis, or so I thought. If you take a bunch of data points and correlate them to re-offend rate there will be some data points that correlate more than others. If one doing the analysis tossed out the data points that had little to no correlation then the accuracy of the predictive value will still be effectively unchanged.
Another thing that I've learned, and I'll admit is controversial to the SJWs out there, is the correlations between ethnicity and intelligence, and between criminal tendencies and intelligence. This is not controversial to the people that do this analysis, it's been established with considerable evidence. It's controversial because people equate "ethnicity" and "race", which are not the same thing. Those with an IQ around 85 or 90 (depending on who you ask) will be most likely to be criminals. Above that IQ there is greater profit in getting a job. Below that IQ the people will have problems concocting the means to break the law and still come out ahead. People from certain areas of the world will, on average, have a lower IQ. Average IQ, by definition, is 100.
If these people want a more accurate indication of criminal behavior then give an IQ test. They won't do that though because people with a certain ethnic background will "fail" this test and be considered more likely to offend. With this trend of ethnic background having some correlation to skin color this algorithm would immediately be considered "racist" and be tossed out by the SJWs. Even though it would be highly accurate in determining future criminal behavior we can't tolerate a "racist" algorithm.
Why do we see more people with dark skin in prisons? Not because of some inherent racism. It's because low IQ people are more likely to break the law, and people with dark skin tend to have a lower IQ. This should not reflect on any individual because "trend" does not mean "will" or "did". Also, even with a 90 average IQ in a population still leaves a lot of room on a bell curve for many geniuses in that population.
Posted anonymously because I'm sure just mentioning these indisputable facts will likely get me labeled a racist.
That missing piece of information was hinted at in the article, race. Although I doubt that it was really race that is the missing piece of data but something else that correlates with race. Perhaps that is education, income, intelligence, size of family, religious background, or having a single parent. It seems they tossed out this racial data because it tended to rate black criminals as more likely to offend. When they did that then they made the algorithm less accurate.
Well facts don't care about your feelings. I suggest they put on their big boy pants and admit to themselves that sometimes race and whatever this factor is that correlates to race is not the same thing. If we are letting people out into the public that have a tendency to re-offend because of their skin color then we are putting the public at risk to avoid hurting people's feelings.
What an idiot. The evidence is very clear: Hillary was a Russian agent. Why the hell else would her husband tell Trump to run, sabotage a very popular Dem candidate, and then have her campaign tell the media to take Trump seriously if she wasn't working for them?
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