Tweak alpha definition again

web/metrics.js

@@ -4,9 +4,9 @@ const metrics = {
     displayName: String.raw`\alpha`,
     displayBody: p => String.raw`
       \frac{
-        \sigma\left(${p}\right)^{1 - (C\left(\left\{\vec{q}\right\}\right) - L\left(\left\{\vec{q}\right\}\right))}
+        \sigma\left(${p}\right)^{1 - C\left(\left\{\vec{q}\right\}\right) L\left(\left\{\vec{q}\right\}\right)}
       }{
-        \Theta\left(${p}\right)^{-1 - (C\left(\left\{\vec{q}\right\}\right) - L\left(\left\{\vec{q}\right\}\right))}
+        \Theta\left(${p}\right)^{-1 - C\left(\left\{\vec{q}\right\}\right) L\left(\left\{\vec{q}\right\}\right)}
       }
     `,
     evaluate: () => 0, // calculated below
@@ -131,7 +131,7 @@ const applyMetrics = (data, target) => {
     Object.entries(metrics)
       .map(([name, metric]) => [name, metric.evaluate(data, target)])
   );
-  const power = target.chroma - target.lightness;
+  const power = target.chroma * target.lightness;
   scores.alpha = Math.pow(scores.sigma, 1 - power) * Math.pow(scores.bigTheta, 1 + power);
   return scores;
 };