Barilliance eCommerce Personalization Blog » Product recommendations

Recommendation engine for e-commerce sites, build vs. buy?

Ido Ariel — Sun, 31 Jan 2010 16:05:36 +0000

Some of the online retailers we talk to, realize the value of cross-sells and up-sells and decide to embark on a “DIY path”. I may be biased here but I think product recommendations are one area in which you don’t want to reinvent the wheel.

There are 2 reasons why a DIY approach does not make sense in this case. The first is the development cost of building a system that works, and the second is the learning curve of optimizing it.

So how difficult is it to develop a recommendation engine? online retailers who decide to build a recommendation engine are not aware of the various components that need to be in place. Here are just a few them:

The recommendation engine should track every major activity shoppers perform on the site including viewed products, categories and brands; items added to the shopping cart and purchased ; search keywords they used ; traffic source visitors arrived from, Geo-location data, and the list goes on…
The system must support multiple recommendation types and should be able to display the right one (and more than one on a single page) based on where the user is at the purchase funnel (if you have less than 10 algorithms your system is extremely naive)
Finding correlations between items/users is easy. The hard part is to choose which correlations should be taken into account and which should be ignored
The system should have built in a/b testing and reporting capabilities so that it could be optimized and demonstrate its value. This point is very critical as few online retailers actually measure the impact of their homegrown systems
The system should have an interface that allows marketers to control the outputs of the recommendation engine based on different variables.

The second reason I mentioned is the experience it takes to optimize such a system. There are many things that will determine the impact a recommendation engine will have on the business, and if it’s your first time building one and it’s a one-off project there is no chance you are going to know them or invest the time to learn them. In fact you are probably going to develop a very naive system and you’ll stay with v1 for a long time. You will not test different widget designs or various placements on the page.

The decision to build or buy a recommendation engine should be ROI based. You need to consider the impact it will have on your business versus the cost of development. Building a very naive system may seem cheap but will also likely to deliver poor results and without supporting systems you’ll never know it.

Product recommendations on out of stock pages

Ido Ariel — Sun, 27 Dec 2009 10:19:05 +0000

Do you measure how many out of stock page views (i.e. out of stock products which are being viewed by your visitors) you receive per day?

Consider shoppers who search for a specific product on Google, find you on on the search results page or an ad, click on it, arrive to your site only to discover that the product is out of stock. This is a disappointing experience for the shopper and a missed opportunity for your business.

So what can you do about it?

1. Probably the best thing you can do is show alternative product recommendations at very prominent position in the product page (above the fold is highly recommended). So when people arrive to an out of stock product page they immediately see the alternatives and chances are your bounce rate will come down.

2. Another action you can take is to allow shoppers to get notifications when the product is back in stock. By doing this you engage customers and build up your permission based marketing database at the same time

3. Consider offering a coupon for first time visitors who landed on an out of stock page but purchased a similar product during the same session

Product Recommendations titles

Ido Ariel — Sun, 20 Dec 2009 14:38:44 +0000

What should be the text of product recommendations titles? should it be a generic “You might also like” or should you provide Amazon style titles such as “Inspired by your shopping cart” or “People who viewed this product also viewed?”

The benefits of the Amazon approach are mainly:

Trustworthiness as recommendations are not provided by the merchant. They are based on the “wisdom of the crowd”
Transparency, shoppers are informed why products are being recommended to them

Those who prefer the “You may also like” approach think the Amazon approach might raise privacy concerns. We don’t think so and recommend our customers to go with transparent titles that clearly explain customers why a set of products are being recommended to them.