anchor.diff:  
   ## Collecting Data
   
  -Next, let's collect some training data for the app of this Engine. By default,
  -the E-Commerce Recommendation Engine Template supports 2 types of entities: **user** and
  -**item**, events **view** and **buy**. An item has the **categories** property, which is a list of category names (String). A user can view and buy an item.
  -
  -There is also one specical **constraint** entiy with entityId **unavailableItems**, which defines a list of unavailable items and is taken into account in real time during serving.
  +Next, let's collect training data for this Engine. By default,
  +the E-Commerce Recommendation Engine Template supports 2 types of entities and 2 events: **user** and
  +**item**; events **view** and **buy**. An item has the **categories** property, which is a list of category names (String). A user can view and buy an item.
  +
  +There is also one specical **constraint** entiy with entityId **unavailableItems**, which defines a list of unavailable items and is taken into account in realtime during serving.
   
   <%= partial 'shared/quickstart/install_sdk' %>
   
  
positive.code: Input Query:
  
  - UserID
  - num of items to be recommended
  - List of white-listed item categories (optional)
  - List of white-listed ItemIds (optional)
  - List of black-listed ItemIds (optional)
  
  The template also supports black-list and white-list. If a white-list is provided, the engine will include only those products in the recommendation.
  Likewise, if a black-list is provided, the engine will exclude those products in the recommendation.
  
  Output PredictedResult:
  
  - a ranked list of recommended itemIDs
  
  ### Predictive Model Training
  
  
negative.code: 
  ## Overview
  
  This engine template provides personalized recommendation for e-commerce applications with the following features by default:
  
  - Exclude out-of-stock items
  - Provide recommendation to new users who sign up after the model is trained
  - Recommend unseen items only
  
  WARNING: This template requires PredictionIO version >= 0.8.7
  
  