![\"\"](\"https:\/\/cn.hostease.com\/xueyuan\/wp-content\/uploads\/2017\/01\/128.png\")
<\/a><\/figure>\n\n\n\n<\/a><\/figure>\n\n\n\n<\/p>\n\n\n\n
\u4e00\uff1a\u6982\u5ff5<\/p>\n\n\n\n
SlopeOne\u7684\u601d\u60f3\u5f88\u7b80\u5355\uff0c\u5c31\u662f\u7528\u5747\u503c\u5316\u7684\u601d\u60f3\u6765\u63a9\u76d6\u4e2a\u4f53\u7684\u6253\u5206\u5dee\u5f02\uff0c\u4e3e\u4e2a\u4f8b\u5b50\u8bf4\u660e\u4e00\u4e0b\uff1a<\/p>\n\n\n\n <\/p>\n\n\n\n \u5728\u8fd9\u4e2a\u56fe\u4e2d\uff0c\u7cfb\u7edf\u8be5\u5982\u4f55\u8ba1\u7b97\u201c\u738b\u4e94\u201c\u5bf9\u201d\u7535\u51b0\u7bb1\u201c\u7684\u6253\u5206\u503c\u5462\uff1f\u521a\u624d\u6211\u4eec\u4e5f\u8bf4\u4e86\uff0cslopeone\u662f\u91c7\u7528\u5747\u503c\u5316\u7684\u601d\u60f3,\u4e5f\u5c31\u662f\uff1aR\u738b\u4e94<\/sub> =4-{[(5-10)+(4-5)]\/2}=7 \u3002<\/p>\n\n\n\n \u4e0b\u9762\u6211\u4eec\u770b\u770b\u591a\u4e8e\u4e24\u9879\u7684\u5546\u54c1\uff0c\u5982\u4f55\u8ba1\u7b97\u6253\u5206\u503c\u3002<\/p>\n\n\n\n rb<\/sub> = (n * (ra<\/sub> – R(A->B<\/sub>)) + m * (rc<\/sub> – R(C->B<\/sub>)))\/(m+n)<\/p>\n\n\n\n \u6ce8\u610f\uff1a a,b,c \u4ee3\u8868\u201c\u5546\u54c1\u201d\u3002<\/p>\n\n\n\n ra<\/sub> \u4ee3\u8868\u201c\u5546\u54c1\u7684\u6253\u5206\u503c\u201d\u3002<\/p>\n\n\n\n ra->b<\/sub> \u4ee3\u8868\u201cA\u7ec4\u5230B\u7ec4\u7684\u5e73\u5747\u5dee\uff08\u5747\u503c\u5316\uff09\u201d\u3002<\/p>\n\n\n\n m,n \u4ee3\u8868\u4eba\u6570\u3002<\/p>\n\n\n\n <\/p>\n\n\n\n \u6839\u636e\u516c\u5f0f\uff0c\u6211\u4eec\u6765\u7b97\u4e00\u4e0b\u3002<\/p>\n\n\n\n r\u738b\u4e94<\/sub> = (2 * (4 – R(\u6d17\u8863\u673a->\u5f69\u7535)) + 2 * (10 – R(\u7535\u51b0\u7bb1->\u5f69\u7535))+ 2 * (5 – R(\u7a7a\u8c03->\u5f69\u7535)))\/(2+2+2)=6.8<\/p>\n\n\n\n \u662f\u7684\uff0cslopeOne\u5c31\u662f\u8fd9\u4e48\u7b80\u5355\uff0c\u5b9e\u6218\u6548\u679c\u975e\u5e38\u4e0d\u9519\u3002<\/p>\n\n\n\n <\/p>\n\n\n\n \u4e8c\uff1a\u5b9e\u73b0<\/p>\n\n\n\n 1\uff1a\u5b9a\u4e49\u4e00\u4e2a\u8bc4\u5206\u7c7bRating\u3002<\/p>\n\n\n\n 2\uff1a \u5b9a\u4e49\u4e00\u4e2a\u4ea7\u54c1\u7c7b<\/p>\n\n\n\n 3\uff1aSlopeOne\u7c7b<\/p>\n\n\n\n \u53c2\u8003\u4e86\u7f51\u7edc\u4e0a\u7684\u4f8b\u5b50\uff0c\u5c06\u4e8c\u7ef4\u77e9\u9635\u505a\u6210\u7ebf\u6027\u8868\uff0c\u6709\u6548\u7684\u964d\u4f4e\u4e86\u7a7a\u95f4\u590d\u6742\u5ea6\u3002<\/p>\n\n\n\n <\/p>\n\n\n\n <\/p>\n\n\n\n 4: \u6d4b\u8bd5\u7c7bProgram<\/p>\n\n\n\n \u8fd9\u91cc\u6211\u4eec\u704c\u5165\u4e86userid=1000\uff0c2000\uff0c3000\u7684\u8fd9\u4e09\u4e2a\u4eba\uff0c\u7136\u540e\u6211\u4eec\u9884\u6d4buserID=3000\u8fd9\u4e2a\u4eba\u5bf9 \u201c\u5f69\u7535\u201d \u7684\u6253\u5206\u4f1a\u662f\u591a\u5c11\uff1f<\/p>\n\n\n\n <\/p>\n\n\n\n <\/p>\n\n\n\n \u76f8\u4fe1\u5927\u5bb6\u5bf9\u5982\u4e0b\u7684Category\u90fd\u5f88\u719f\u6089\uff0c\u5f88\u591a\u7f51\u7ad9\u90fd\u6709\u7c7b\u4f3c\u5982\u4e0b\u7684\u529f\u80fd\uff0c\u201c\u5546\u54c1\u63a8\u8350\u201d,”\u731c\u4f60\u559c\u6b22\u201c\uff0c … \u9605\u8bfb\u66f4\u591a<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[5],"tags":[],"class_list":["post-1710","post","type-post","status-publish","format-standard","hentry","category-jishu"],"aioseo_notices":[],"jetpack_featured_media_url":"","jetpack-related-posts":[],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/cn.hostease.com\/xueyuan\/wp-json\/wp\/v2\/posts\/1710","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cn.hostease.com\/xueyuan\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/cn.hostease.com\/xueyuan\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/cn.hostease.com\/xueyuan\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/cn.hostease.com\/xueyuan\/wp-json\/wp\/v2\/comments?post=1710"}],"version-history":[{"count":3,"href":"https:\/\/cn.hostease.com\/xueyuan\/wp-json\/wp\/v2\/posts\/1710\/revisions"}],"predecessor-version":[{"id":9265,"href":"https:\/\/cn.hostease.com\/xueyuan\/wp-json\/wp\/v2\/posts\/1710\/revisions\/9265"}],"wp:attachment":[{"href":"https:\/\/cn.hostease.com\/xueyuan\/wp-json\/wp\/v2\/media?parent=1710"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cn.hostease.com\/xueyuan\/wp-json\/wp\/v2\/categories?post=1710"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cn.hostease.com\/xueyuan\/wp-json\/wp\/v2\/tags?post=1710"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}<\/a><\/figure>\n\n\n\n<\/a><\/figure>\n\n\n\n 1 \/\/\/ <summary>\n 2 \/\/\/ \u8bc4\u5206\u5b9e\u4f53\u7c7b\n 3 \/\/\/ <\/summary>\n 4 public class Rating\n 5 {\n 6 \/\/\/ <summary>\n 7 \/\/\/ \u8bb0\u5f55\u5dee\u503c\n 8 \/\/\/ <\/summary>\n 9 public float Value { get; set; }\n10 \n11 \/\/\/ <summary>\n12 \/\/\/ \u8bb0\u5f55\u8bc4\u5206\u4eba\u6570\uff0c\u65b9\u4fbf\u516c\u5f0f\u4e2d\u7684 m \u548c n \u7684\u503c\n13 \/\/\/ <\/summary>\n14 public int Freq { get; set; }\n15 \n16 \/\/\/ <summary>\n17 \/\/\/ \u8bb0\u5f55\u6253\u5206\u7528\u6237\u7684ID\n18 \/\/\/ <\/summary>\n19 public HashSet<int> hash_user = new HashSet<int>();\n20 \n21 \/\/\/ <summary>\n22 \/\/\/ \u5e73\u5747\u503c\n23 \/\/\/ <\/summary>\n24 public float AverageValue\n25 {\n26 get { return Value \/ Freq; }\n27 }\n28 }<\/pre>\n 1 \/\/\/ <summary>\n 2 \/\/\/ \u4ea7\u54c1\u7c7b\n 3 \/\/\/ <\/summary>\n 4 public class Product\n 5 {\n 6 public int ProductID { get; set; }\n 7 \n 8 public string ProductName { get; set; }\n 9 \n10 \/\/\/ <summary>\n11 \/\/\/ \u5bf9\u4ea7\u54c1\u7684\u6253\u5206\n12 \/\/\/ <\/summary>\n13 public float Score { get; set; }\n14 }<\/pre>\n<\/a><\/figure>\n\n\n\n 1 using System;\n 2 using System.Collections.Generic;\n 3 using System.Linq;\n 4 using System.Text;\n 5 \n 6 namespace SupportCenter.Test\n 7 {\n 8 #region Slope One \u7b97\u6cd5\n 9 \/\/\/ <summary>\n 10 \/\/\/ Slope One \u7b97\u6cd5\n 11 \/\/\/ <\/summary>\n 12 public class SlopeOne\n 13 {\n 14 \/\/\/ <summary>\n 15 \/\/\/ \u8bc4\u5206\u7cfb\u7edf\n 16 \/\/\/ <\/summary>\n 17 public static Dictionary<int, Product> dicRatingSystem = new Dictionary<int, Product>();\n 18 \n 19 public Dictionary<string, Rating> dic_Martix = new Dictionary<string, Rating>();\n 20 \n 21 public HashSet<int> hash_items = new HashSet<int>();\n 22 \n 23 #region \u63a5\u6536\u4e00\u4e2a\u7528\u6237\u7684\u6253\u5206\u8bb0\u5f55\n 24 \/\/\/ <summary>\n 25 \/\/\/ \u63a5\u6536\u4e00\u4e2a\u7528\u6237\u7684\u6253\u5206\u8bb0\u5f55\n 26 \/\/\/ <\/summary>\n 27 \/\/\/ <param name=\"userRatings\"><\/param>\n 28 public void AddUserRatings(IDictionary<int, List<Product>> userRatings)\n 29 {\n 30 foreach (var user1 in userRatings)\n 31 {\n 32 \/\/\u904d\u5386\u6240\u6709\u7684Item\n 33 foreach (var item1 in user1.Value)\n 34 {\n 35 \/\/\u8be5\u4ea7\u54c1\u7684\u7f16\u53f7\uff08\u5177\u6709\u552f\u4e00\u6027\uff09\n 36 int item1Id = item1.ProductID;\n 37 \n 38 \/\/\u8be5\u9879\u76ee\u7684\u8bc4\u5206\n 39 float item1Rating = item1.Score;\n 40 \n 41 \/\/\u5c06\u4ea7\u54c1\u7f16\u53f7\u5b57\u5b58\u653e\u5728hash\u8868\u4e2d\n 42 hash_items.Add(item1.ProductID);\n 43 \n 44 foreach (var user2 in userRatings)\n 45 {\n 46 \/\/\u518d\u6b21\u904d\u5386item\uff0c\u7528\u4e8e\u8ba1\u7b97\u4fe9\u4fe9 Item \u4e4b\u95f4\u7684\u5dee\u503c\n 47 foreach (var item2 in user2.Value)\n 48 {\n 49 \/\/\u8fc7\u6ee4\u6389\u540c\u540d\u7684\u9879\u76ee\n 50 if (item2.ProductID <= item1Id)\n 51 continue;\n 52 \n 53 \/\/\u8be5\u4ea7\u54c1\u7684\u540d\u5b57\n 54 int item2Id = item2.ProductID;\n 55 \n 56 \/\/\u8be5\u9879\u76ee\u7684\u8bc4\u5206\n 57 float item2Rating = item2.Score;\n 58 \n 59 Rating ratingDiff;\n 60 \n 61 \/\/\u7528\u8868\u7684\u5f62\u5f0f\u6784\u5efa\u77e9\u9635\n 62 var key = Tools.GetKey(item1Id, item2Id);\n 63 \n 64 \/\/\u5c06\u4fe9\u4fe9 Item \u7684\u5dee\u503c \u5b58\u653e\u5230 Rating \u4e2d\n 65 if (dic_Martix.Keys.Contains(key))\n 66 ratingDiff = dic_Martix[key];\n 67 else\n 68 {\n 69 ratingDiff = new Rating();\n 70 dic_Martix[key] = ratingDiff;\n 71 }\n 72 \n 73 \/\/\u65b9\u4fbf\u4ee5\u540e\u4ee5\u540euserrating\u7684\u7f16\u8f91\u64cd\u4f5c\uff0c\uff08add)\n 74 if (!ratingDiff.hash_user.Contains(user1.Key))\n 75 {\n 76 \/\/value\u4fdd\u5b58\u5dee\u503c\n 77 ratingDiff.Value += item1Rating - item2Rating;\n 78 \n 79 \/\/\u8bf4\u660e\u8ba1\u7b97\u8fc7\u4e00\u6b21\n 80 ratingDiff.Freq += 1;\n 81 }\n 82 \n 83 \/\/\u8bb0\u5f55\u64cd\u4f5c\u4eba\u7684ID\uff0c\u65b9\u4fbf\u4ee5\u540e\u518d\u6b21\u6dfb\u52a0\u8bc4\u5206\n 84 ratingDiff.hash_user.Add(user1.Key);\n 85 }\n 86 }\n 87 }\n 88 }\n 89 }\n 90 #endregion\n 91 \n 92 #region \u6839\u636e\u77e9\u9635\u7684\u503c\uff0c\u9884\u6d4b\u51fa\u8be5Rating\u4e2d\u7684\u503c\n 93 \/\/\/ <summary>\n 94 \/\/\/ \u6839\u636e\u77e9\u9635\u7684\u503c\uff0c\u9884\u6d4b\u51fa\u8be5Rating\u4e2d\u7684\u503c\n 95 \/\/\/ <\/summary>\n 96 \/\/\/ <param name=\"userRatings\"><\/param>\n 97 \/\/\/ <returns><\/returns>\n 98 public IDictionary<int, float> Predict(List<Product> userRatings)\n 99 {\n100 Dictionary<int, float> predictions = new Dictionary<int, float>();\n101 \n102 var productIDs = userRatings.Select(i => i.ProductID).ToList();\n103 \n104 \/\/\u5faa\u73af\u904d\u5386_Items\u4e2d\u6240\u6709\u7684Items\n105 foreach (var itemId in this.hash_items)\n106 {\n107 \/\/\u8fc7\u6ee4\u6389\u4e0d\u9700\u8981\u8ba1\u7b97\u7684\u4ea7\u54c1\u7f16\u53f7\n108 if (productIDs.Contains(itemId))\n109 continue;\n110 \n111 Rating itemRating = new Rating();\n112 \n113 \/\/ \u5185\u5c42\u904d\u5386userRatings\n114 foreach (var userRating in userRatings)\n115 {\n116 if (userRating.ProductID == itemId)\n117 continue;\n118 \n119 int inputItemId = userRating.ProductID;\n120 \n121 \/\/\u83b7\u53d6\u8be5key\u5bf9\u5e94\u9879\u76ee\u7684\u4e24\u7ec4AVG\u7684\u503c\n122 var key = Tools.GetKey(itemId, inputItemId);\n123 \n124 if (dic_Martix.Keys.Contains(key))\n125 {\n126 Rating diff = dic_Martix[key];\n127 \n128 \/\/\u5173\u952e\u70b9\uff1a\u8fd0\u7528\u516c\u5f0f\u6c42\u89e3\uff08\u8fd9\u8fb9\u4e3a\u4e86\u8282\u7701\u7a7a\u95f4\uff0c\u5bf9\u89d2\u7ebf\u4e24\u4fa7\u7684\u503c\u5448\u73b0\u5947\u51fd\u6570\u7684\u7279\u6027\uff09\n129 itemRating.Value += diff.Freq * (userRating.Score + diff.AverageValue * ((itemId < inputItemId) ? 1 : -1));\n130 \n131 \/\/\u5173\u952e\u70b9\uff1a\u8fd0\u7528\u516c\u5f0f\u6c42\u89e3 \u7d2f\u8ba1\u6bcf\u4e24\u7ec4\u7684\u4eba\u6570\n132 itemRating.Freq += diff.Freq;\n133 }\n134 }\n135 \n136 predictions.Add(itemId, itemRating.AverageValue);\n137 }\n138 \n139 return predictions;\n140 }\n141 #endregion\n142 }\n143 #endregion\n144 \n145 #region \u5de5\u5177\u7c7b\n146 \/\/\/ <summary>\n147 \/\/\/ \u5de5\u5177\u7c7b\n148 \/\/\/ <\/summary>\n149 public class Tools\n150 {\n151 public static string GetKey(int Item1Id, int Item2Id)\n152 {\n153 return (Item1Id < Item2Id) ? Item1Id + \"->\" + Item2Id : Item2Id + \"->\" + Item1Id;\n154 }\n155 }\n156 #endregion\n157 }<\/pre>\n 1 public class Program\n 2 {\n 3 static void Main(string[] args)\n 4 {\n 5 SlopeOne test = new SlopeOne();\n 6 \n 7 Dictionary<int, List<Product>> userRating = new Dictionary<int, List<Product>>();\n 8 \n 9 \/\/\u7b2c\u4e00\u4f4d\u7528\u6237\n10 List<Product> list = new List<Product>()\n11 {\n12 new Product(){ ProductID=1, ProductName=\"\u6d17\u8863\u673a\",Score=5},\n13 new Product(){ ProductID=2, ProductName=\"\u7535\u51b0\u7bb1\", Score=10},\n14 new Product(){ ProductID=3, ProductName=\"\u5f69\u7535\", Score=10},\n15 new Product(){ ProductID=4, ProductName=\"\u7a7a\u8c03\", Score=5},\n16 };\n17 \n18 userRating.Add(1000, list);\n19 \n20 test.AddUserRatings(userRating);\n21 \n22 userRating.Clear();\n23 userRating.Add(1000, list);\n24 \n25 test.AddUserRatings(userRating);\n26 \n27 \/\/\u7b2c\u4e8c\u4f4d\u7528\u6237\n28 list = new List<Product>()\n29 {\n30 new Product(){ ProductID=1, ProductName=\"\u6d17\u8863\u673a\",Score=4},\n31 new Product(){ ProductID=2, ProductName=\"\u7535\u51b0\u7bb1\", Score=5},\n32 new Product(){ ProductID=3, ProductName=\"\u5f69\u7535\", Score=4},\n33 new Product(){ ProductID=4, ProductName=\"\u7a7a\u8c03\", Score=10},\n34 };\n35 \n36 userRating.Clear();\n37 userRating.Add(2000, list);\n38 \n39 test.AddUserRatings(userRating);\n40 \n41 \/\/\u7b2c\u4e09\u4f4d\u7528\u6237\n42 list = new List<Product>()\n43 {\n44 new Product(){ ProductID=1, ProductName=\"\u6d17\u8863\u673a\", Score=4},\n45 new Product(){ ProductID=2, ProductName=\"\u7535\u51b0\u7bb1\", Score=10},\n46 new Product(){ ProductID=4, ProductName=\"\u7a7a\u8c03\", Score=5},\n47 };\n48 \n49 userRating.Clear();\n50 userRating.Add(3000, list);\n51 \n52 test.AddUserRatings(userRating);\n53 \n54 \/\/\u90a3\u4e48\u6211\u4eec\u9884\u6d4buserID=3000\u8fd9\u4e2a\u4eba\u5bf9 \u201c\u5f69\u7535\u201d \u7684\u6253\u5206\u4f1a\u662f\u591a\u5c11\uff1f\n55 var userID = userRating.Keys.FirstOrDefault();\n56 var result = userRating[userID];\n57 \n58 var predictions = test.Predict(result);\n59 \n60 foreach (var rating in predictions)\n61 Console.WriteLine(\"ProductID= \" + rating.Key + \" Rating: \" + rating.Value);\n62 }\n63 }<\/pre>\n<\/a><\/figure>\n\n\n\n
\u6587\u7ae0\u6765\u81ea\u7f51\u7edc\u535a\u5ba2\uff0c\u539f\u6587\u5730\u5740\uff1ahttps:\/\/www.cnblogs.com\/huangxincheng\/archive\/2012\/11\/22\/2782647.html<\/p>\n","protected":false},"excerpt":{"rendered":"