Github user coderh commented on the pull request:
https://github.com/apache/spark/pull/597#issuecomment-45898782
Ok, I have found the error in my metric.
```
val itemFactors = model.productFeatures.collect()
```
This line is for creating a item-factor matrix, the problem is that item
factors are not ordered by item id when collecting them, which leads to a wrong
matrix, that's y the result is non sense.
Adding a sortBy(_._1), like
```
val itemFactors = model.productFeatures.collect().sortBy(_._1)
```
give a EPR like 9%(in sample), 10%(out of sample)
Implicit ALS works. Thanks.
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