neo4j - Recommendation Engine: Cosine Similarity vs Measuring %difference between each vector component -

-

Let's say I have a database of users who evaluate different products on a scale of 1-5, our recommendation engine users Recommends products that are very similar on the basis of other users' preferences. My first method was to use cosine parity to find similar users, and user evaluation was to be used as vector components only. The main problem with this approach is that it only measures the vector angles and does not take into account the rating scale or magnitude.

My question is: Can someone explain (Users) to measure percentage difference between vector components Why is there a better cosine similarity to identify user similarity?

For example, why not do this: 

  n = 5 wire one = (1,4,4) B = (2,3,4) similarity (A, B) = 1 - ((| 1-2 | / 5) + (| 4-3 | / 5) + (| 4-4 | / 5)) / 3 = .86667   
  Instead of cosine similarity:   
  a = (1,4,4) = B (2 , 3,4) Cosciemiracy (A, B) = (1 * 2) + (4 * 3) + (4 * 4) / sqrt ((1 ^ 2) + (4 ^ 2) + (4 ^ 2)) * SQLT ((2 ^ 2) + (3 ^ 2) + (4 ^ 2)) = 979    
 
 
 I find an answer that all the recommendations do not work on the rating on problems 1-5, and all the originals Do not work feature space at all, but sometimes low-rank facility in place. The answer is changed there.  
 I do not think cosine is a great metric for equality ratings. The rating is not something that you want to normalize. It makes a bit more sense if you consider each user's rating as normal 0.  
 I'm not sure whether this type of modified L1 is optimal to use distance, either to look at the normal Euclidean / L2 distance. In the end, the empirical test will tell you that the most for your data What is good

Comments

Post a Comment

Popular posts from this blog

php - PDO bindParam() fatal error -

-
I am trying to learn PDO, now I have written this small code, but it gives me a serious error: < P> Fatal error: Call a member function at a non-object dot () ... $ con = new mysqli ("127.0.0.1", "root", "", "csvdangercheck"); $ Query = $ con- & gt; ("Id,` var1`, `var2`) values ​​(" id,: var1,: var2) ";); $ query- & gt; bypass pattern (': id', $ id); $ query- & gt; BindParam (': var1', $ VAL1); $ Query- & gt; bindParam (': var2', $ val2); $ Query-> Executed (); I Trying to use print_r ($ con-> errorInfo ()) but Fatal error: Undefined method mysqli :: errorInfo ( ) ... can someone tell me what am I missing? Flaffeh said, you have PDO Missing Mysqy, try it: $ con = new PDO ('mysql: host = 127.0.0.1; dbname = csvdangercheck', 'root', '');
Read more

logging - How can I log both the Request.InputStream and Response.OutputStream traffic in my ASP.NET MVC3 Application for specific Actions? -

-
For a specific set of tasks, I need to log in to the incoming request inputstream as well as outgoing response. is. I am using an ActionFilterAttribute for this and overriding the OnActionExecuted and OnResultExecuted methods. So I'm starting with this idea ... Public category ActionLoggerAttribute: ActionFilterArrbit {Public Override Zero On-Offed Execution (ActionActioned Contact Filter Filter) {base.OnActionAxecuted (FilterContext); HttpRequestBase request = filterContext.HttpContext.Request; // TODO: Log the request. InputStream} Public Override Zero OnResultExecuted (ResultExecutedContext FilterContext) {base.OnResultExecuted (filterContext); HTTPRPSPointBase Response = FilterContacts Hpptex response; // TODO: Log on Response.OutputStream}} Ideally I'll hook it up with enterprise library logging because I'm already using it for error logging. Am I reaching the input and output stream at the right time? Can I easily use the Enterprise Library to log i
Read more

java - Why my included JSP file won't get processed correctly? -

-
I am trying to create Java web framework (and learning), and on the basis of 'Code Generator In the process of making the material view of the database in the process of development, I stumbled into a difficulty, which I do not know how to solve it. First of all, I want the following index.jsp : & lt; Body & gt; Use all pages to be created. & Lt;% @ include file = "header.jsp"% & gt; & Lt; Hours / & gt; & Lt;% @ included file = "body.jsp"%> & Lt; Hours / & gt; & Lt;% @ include file = "footer.jsp"% & gt; & Lt; / Body & gt; And, in body.jsp , I should have it like this: & lt; Jsp: include page = "$ {Application_modul}"%> Where application_modul is an attribute defined in its controller: request.setAttribute ("application_modul", "USER_ACCOUNT \\ ' View_user_account.jsp "); This file can be found properly, but the processed JSP does
Read more