anchor.diff:  the Recommendation Engine Template supports 2 types of events: **rate** and
   **buy**. A user can give a rating score to an item or buy an item. This template requires user-view-item and user-buy-item events.
   
  -INFO: This template can easily be customized to consider more user events such as *like*, *dislike* etc.
  +INFO: This template can easily be customized to consider more user events such as *like*, *dislike*, etc.
   
   <%= partial 'shared/quickstart/collect_data' %>
   
  
positive.code: 
  ## 6. Use the Engine
  
  Now, You can try to retrieve predicted results. To recommend 4 movies to user
  whose id is 1, you send this JSON `{ "user": "1", "num": 4 }` to the deployed
  engine and it will return a JSON of the recommended movies. Simply send a query
  by making a HTTP request or through the `EngineClient` of an SDK.
  
  With the deployed engine running, open another terminal and run the following `curl` command or use SDK to send the query:
  
  <div class="tabs">
    <div data-tab="REST API" data-lang="json">
  
negative.code: - user 'rate' item events
  - user 'buy' item events
  
  NOTE: You can customize this engine to use other events.
  
  ### Input Query
  
  - user ID
  - number of recommended items
  
  ### Output PredictedResult
  
  