How to predict customer's next purchase Suppose we want to predict what customer will buy during his next visit to the Electronic Shop based on his past purchase history. I know that it is a very broad question, but I am new to machine learning and don't have much idea about how to approach this problem.

The simplest thing that comes to my mind is to find the most frequent items that customer has bought and suggest it. However, I don't think that this is a very robust approach as it doesn't consider this scenario:

Computer (1st Purchase) -&gt; Mouse (2nd Purchase) -&gt; Mouse Pad (3rd Purchase)


I am looking for a simple model to get started and scale in terms of features and training data. I would love to hear suggestions of experienced Data Scientist as it is a most common problem.

Thank you.
Take a look at association rule learning (https://en.wikipedia.org/wiki/Association_rule_learning). A really common algorithm is the Apriori agorithm. You could use the package apyori, it works great: https://pypi.python.org/pypi/apyori/1.1.1