F-成绩和准确度

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在Eyewire,您将获得基于您的F分数的准确率评级。F分数是决定准确度占准确率和召回这两种统计方法。或者更简单地说,F分数是HQ根据添加多的、缺失的模块来决定你的准确率。传统F分数的公式为:

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在计算最终的F分数时,要提前计算好玩家个人的准确率和召回。方块由玩家搭建完后,程序识别并输出4种判断的结果:正确的阳性结果、错误的阳性结果、正确的阴性结果、错误的阴性结果。正确的阳性结果(tp)是你正确添加的小区块个数;错误的阳性结果(fp)是你错误添加了不该有的小区块;正确的阴性结果(tn)是你移除原来模型中错误的小区块;错误的阴性结果(fn)是你遗漏了需要添加的小区块。你可以在下图看到错误的阳性与错误的阴性的区别。


NewFScoreEyeWire.png
左边是玩家提交的一个方块。 这个示例中,绿色和红色是玩家已经提交的增添了的片段,紫色是玩家遗漏的部分片段。


图中红色片段是假阳性,紫色片段是假阴性。 玩家错误地添加了红色段,而不是区添加紫色片段。 绿色片段正确。


This brings us to precision; precision is how much of a volume was added correctly. For example if Player A has a precision 0.9221 that means about 92% of what Player A added was correct and about 8% of what Player A added should not have been added. To determine a player’s precision we use their true positive (tp) results, correctly added, and their false positive (fp) results, incorrectly added, in this formula:
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Recall measures how much of the volume was missed. Let’s say Player A has a recall of 0.9409. That means that Player A missed about 6% of the correct segments in the cubes Player A worked on. To determine a player’s recall we use their true positive (tp) results, correctly added, and false negative (fn) results, incorrectly missed, in this formula:
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Now we would take the results from both of those formulas and plug them into the formula above to get a player’s F-score. Another way to look at it is we take the harmonic mean of a player’s precision and recall to get their overall accuracy rating.

How Accurate are F-Scores?

One question we a get a lot is how do we know what is correct and what isn’t? What is correct is determined by combining the GrimReaper’s corrections with the EyeWirer consensus. If a cube does not have a GrimReaper correction we just use the EyeWirer consensus. EyeWire consensuses have proven to be quite accurate. However, there is still a small chance that a consensus may contain a wrong piece. This means that F-scores cannot prove user accuracy 100% of the time. However, they are accurate enough that we feel confident using them as a player guide.