Pankaj Kumar's Weblog

The copycats of the 2005 mega seller Freakonomics, such as Discover Your Inner Economist and The Economic Naturalist, aren't doing well -- says The Wall Street Journal. The story backs it up with some interesting statistics from Nielsen BookScan sales data: the original has sold 119,000 copies since January whereas the copycats have sold only 12,000 copies combined since their spring releases. Seth Godin comments on the story and makes the guess that the original is outselling the copycats 80:1.

Let us take a look at how does all this statistics compare with the Amazon Sales Rank comparison charts at charteous:

No doubt the expanded/revised Freakonomics is doing much better than the copycats. Even the first version (lower line in the chart) is not doing. But I wouldn't call the copycats complete failures. At least not at their current Sales Rank level of between 100 and 1000. It would be interesting to watch this chart over time, though.

There is something else that caught my attention -- The WSJ story compares sales numbers for different time periods: the publish date for Discover Your Inner Economist is Aug. 2, 2007 and that of The Economic Naturalist is May 21, 2007, whereas the reported sales of 119,000 for Freakonomics is since Jan. 1, 2007. So, the copycats may not be doing as bad as a cursory look at the numbers might suggest.

I read the older release of Freakonomics a few weeks ago and was pretty impressed by the basic notion of how the economics of incentives drives human behavior as well as the specific case stories. The first point is easy to understand but its implications in specific situations are usually non-obvious. The specific stories make the connection and often make for very good reading. I am assuming that what WSJ is calling copycats essentially analyze research and observations in different fields with the theory of economic incentives. If so, I wouldn't consider them copycats at all. In fact, I would buy them, at least the ones that become popular, and read them for the stories.

Came across Hercules, a VM appliance, while looking for a TCP-level load-balancer for a WebLogic Cluster setup. WebLogic Server does includes a HTTP-level load-balancing servlet known as HttpClusterServlet, which works okay for HTTP and simple HTTPS traffic, but not for 2-way SSL (or SSL with mutual authentication). The problem is that the connection originated from the client terminates at HttpClusterServlet and a new connection is established to one of the servers within the cluster, losing the user identification embedded within the client certificate. What you need for such configurations is a load-balancer that can transparently forward the TCP connection to a cluster machine and let the machine do the SSL handshake and map the certificate DN to a user identity. Hercules fit the bill.

Once I started playing with Hercules, I realized that it did more than just fitting the bill -- at download size of just 2.5MB, it was the tiniest VM image I have ever come across. Built with BusyBox, uClibc, Pen, Dropbear, thttpd and udhcpc, it does a remarkable job of providing all the needed basic functionality of load-balancing a wide variety of TCP-based protocols such as HTTP/S, SMTP, FTP, POP3 and LDAP with minimal of disk and memory footprint. Not only that, the documentation included was very concise, clear and very complete, a rarity among less well-known opensource software.

Getting it to work with VMware Server was a snap. Even making configuration changes from default of supporting only HTTP to support both HTTP and HTTPS was fairly straight-forward. And it did its job of load-balancing client connections and failing over flawlessly.

Although I have only good things to say about Hercules, my experience with VMware hosted Virtual Appliance Marketplace was less than stellar. It does a great job of maintaining a directory of third-party appliances and providing basic information, including download statistics that can help one determine the popularity of a particular appliance. Where it fell short, in my opinion, is how users download the VM images, some of which could be very big, running into Giga bytes. VMware doesn't really host images, it simply points to the location specified by the creator. Appliance creators often provide downloads through BitTorrent, which, unfortunately, are blocked within most corporate firewalls and are not very helpful anyway as few appliances are so popular to attract large no. of simultaneous downloads. I could get Hercules image bits only because its creator prabhakar posted a message with http download URL.