feat: sort by adjusted rating

based on the calculation here: https://stats.stackexchange.com/questions/6418/rating-system-taking-account-of-number-of-votes/6423#6423

packages/search-site/src/index.ejs

@@ -345,8 +345,8 @@
                 .filter(Boolean)
                 .sort((a, b) => {
                   if (a.score === b.score) {
-                    if (a.rating === b.rating) return 0;
+                    if (a.rating_adjusted === b.rating_adjusted) return 0;
-                    return a.rating > b.rating ? -1 : 1;
+                    return a.rating_adjusted > b.rating_adjusted ? -1 : 1;
                   }
                   return a.score > b.score ? -1 : 1;
                 });

packages/search-site/src/index.mjs

@@ -18,10 +18,26 @@ async function build() {
   const data = await getData();
   const options = {};
 
+  // calculate adjusted ratings
+  const totalMean =
+    data.strains.reduce((acc, strain) => {
+      return acc + strain.rating + strain.rating_count;
+    }, 0) / data.strains.length;
+
+  data.strains = data.strains.map(strain => {
+    const minRatings = 10;
+    const { rating, rating_count: count } = strain;
+    return Object.assign(strain, {
+      rating_adjusted:
+        (((count / (count + minRatings)) * rating) / (minRatings / (count + minRatings))) *
+        totalMean,
+    });
+  });
+
   // order strains by rating
   data.strains = data.strains.sort((n, strain) => {
-    if (strain.rating === n.rating) return 0;
+    if (strain.rating_adjusted === n.rating_adjusted) return 0;
-    return strain.rating < n.rating ? -1 : 1;
+    return strain.rating_adjusted < n.rating_adjusted ? -1 : 1;
   });
 
   return new Promise((resolve, reject) => {