Since the CFA June exams are now done, there's a lot of concern as to how CFAI determines a passing score. So, here's a breakdown for Levels 1 and 2:
In the past CFAI used a strictly numeric method of calculating the pass rate - they'd take 70% of the 95th percentile score. So, back in the day, the minimum passing score would be no greater than 70%, and would typically be even less.
Now, their scoring system has a significant subjective component to it. Here's how it works: CFA Institute brings a number of charterholders that they call "Standard Setters" to Charlotte sometime in June. These people then discuss what they think a "minimally qualified" candidate should know (for L1 and L2). CFAI is pretty opaque as to what this actually means, but my understanding is that they look at the exams and come up with "the score".
They refer to what's know as the "Angoff method". If they apply this method in its strictest sense, this would involve each standard setter examining each question and making a subjective determination as to what percentage of well-qualified candidates would answer correctly on the question. For each question, the standard-setters percentages are averaged to get a percentage for that question. The individual question-percentages are then summed to get the passing score (in terms of number of correct answers needed).
So theoretically, the minimum passing score could be above 70%. But according to the scuttlebut on analyst forum, the minimum has likely been below 70% in each year. So, my gut reaction is that a 70% would get it done, and even slightly less.
But that's just a guess on my part.
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