Monthly Archives: June 2013

The size and scale of eBay: 2013 edition

It’s time for an update of the eBay Marketplaces interesting statistics that I shared last year. eBay Marketplaces means we’re the team that builds ebay.comebay.co.ukebay.deebay.com.au, and most of the other worldwide marketplaces under the eBay brand.

eBay Marketplaces sold over US$75.3 billion in merchandise in 2012

eBay Marketplaces sold over US$75.3 billion in merchandise in 2012

Here are some refreshed and new facts:

  • We have over 50 petabytes of data stored in our Hadoop and Teradata clusters
  • We have over 400 million items for sale
  • We process more than 250 million user queries per day
  • We serve over 100,000 pages per second
  • Our users spend over 180 years in total every day looking at items
  • We have over 112 million active users
  • We sold over US$75 billion in merchandize in 2012

eBay’s an exciting place to be — plenty of engineering, business, and commerce challenges that are driven by users, items, traffic, and sales. See you next week.

Selling on eBay

I gave a webinar last week on Search at eBay. Thank you to those who attended and asked great questions. The webinar was recorded and you can listen and view the slides here.

Search at eBay. A tour of search from a recent webinar.

Search at eBay. A tour of search from a recent webinar.

In the webinar, I present a background of some of the facts and figures about eBay (an updated version of this post), a short introduction to how search works, and a tour of our current and future search platforms. The talk concludes with over thirty minutes of Q&A. The middle of the talk is dedicated to explaining how to sell successfully on eBay, and I summarize that advice in this post.

Listing for Success in Search

It’s important to remember that search isn’t the only step in selling on eBay. It’s a three-step process:

  1. Finding an item in search
  2. Choosing an item
  3. Purchasing the item

Visibility in search is therefore important, but it isn’t sufficient to guarantee sales. You must also focus on ensuring buyers click on your item and make the choice to purchase it.

On the first point: it’s true that most successful sales begin with a search on eBay, but many others occur through buyers finding items on another search engine, in an email,  through the merchandizing that we feature, or through another source such as a social network. Searches on eBay also don’t always have a keyword: many buyers browse through our categories to find the item they want.

Visibility in Search

Our search team focuses on three tenets of delivering a great experience for our buyers:

  1. Trust: ensuring our buyers get a retail-like experience from great sellers
  2. Value: ensuring our buyers find great deals, including shipping costs
  3. Relevance: ensuring our buyers see items that match what they want

If you focus on these three tenets, you will be successful in gaining visibility in search.

Delivering Trust, Value, and Relevance

Here is some specific advice on how you can be found in search, have your items chosen in search, and drive sales:

  • List in the correct category with a meaningful title; a meaningful title contains only words that accurately describe the item, it omits “spam words” (off-topic words) and isn’t unnecessarily short or long
  • Use item specifics and item condition; we match queries against the item specifics, and to be found successfully we recommended you adopt item specifics
  • When it makes sense for your business, use a long-duration, multi-quantity Buy It Now format
  • Study what it takes to be a Top Rated Seller on eBay; it is our definition of the key tenets of being a trusted seller on eBay, and we use those trust signals in search
  • Have great, large, clear pictures for your listings; we know from many experiments that pictures matter to our buyers, and you’re much more likely to be chosen in search and have sales if your pictures are high-quality
  • Be price competitive; this changes frequently, and you need to understand the market price for your items and be prepared to make changes
  • Specify shipping costs; our customers want great value, and that includes value in shipping
  • Have a clear, structured, and comprehensive item description. Stay “on topic” and describe your item accurately
  • Offer fast shipping and international options; fast shipping matters to our buyers, and offering international options means you have more exposure to more customers

We don’t offer specific answers to specific questions about how Best Match works on eBay. For example, we don’t comment on how we use each of the item specifics in search or whether having certain keywords in certain places in your titles matters. Why not? We want sellers to focus on the key tenets of Trust, Value, and Relevance, and not on specific features that may change or that might give sellers a short-term unfair advantage over other great sellers. Indeed, if a shortcut works today, it may not work tomorrow — we want a level playing field for all sellers, and we’re continually improving Best Match to use more Trust, Value, and Relevance information.

I encourage you to listen to the webinar for a richer explanation of how to sell successfully on eBay with a search-centric focus. See you next week.

Reflecting on my hash table post

My blog post on hash tables was shared 400 times, had 12,000 views in one day, and 28,000 views in the month it was published. There were long threads on reddit and Hacker News.

The sentiment is more negative than positive – folks pointing out that the article was obvious, picking apart one or more points, or stating I don’t know what I’m doing. There are valid points. There are incorrect points too.

This blog went relatively crazy last October. The cause was my post on hash tables.

This blog went relatively crazy last October. The cause was my post on hash tables.

When I speak to people, the sentiment is mostly positive. They thank me for explaining something they’ve long forgotten, and asking them to think before they use a library function.

I enjoy writing simple, accessible posts: my first book sold over 100,000 copies because I wrote plainly in an accessible way. That’s always how I’ve taught too: by explaining through analogy or in simple terms concepts that are complex. I’m just not the guy to explain concepts using math or who’ll offer the shortest, densest, most information-rich explanations.

I agree that my hash table post paints a simplified picture for the average reader. Yes, that makes it problematic at the edges. For example, you’d want to be careful of a hash table’s worst-case complexity in a mission critical or cryptography application. Yes, there are hash functions that distribute string keys better —  this one is reasonable, and I said it was fast. There are other valid points too.

Here’s where I was coming from: Are most developers using a library hash function without thinking about it? I think so. Will reading my article help them think and make better choices? I hope so. That’s the intended audience. No apologies from me — I’ll stir up more trouble soon with a post on how trees work.

See you next week.