Dr. Dobb's | Hard Copy: Ending Spam and Managing Managers

Hard Copy: Ending Spam and Managing Managers

Jonathan looks into Ending Spam, and Adam goes Behind Closed Doors.

September 08, 2006
URL:http://www.drdobbs.com/hard-copy-ending-spam-and-managing-manag/192700269

Ending Spam: Bayesian Content Filtering and the Art of Statistical Language Classification

Jonathan A. Zdziarski

No Starch Press, 2005; 287 pp.; $39.95; ISBN 1593270526

Anyone who has managed to avoid being flooded with spam should consider himself lucky. For everyone else, there is Jonathan Zdziarski's Ending Spam: Bayesian Content Filtering and the Art of Statistical Language Classification. Though the title may be intimidating, the content is both comprehensible and useful.

Zdziarski gives an account of the techniques employed by spammers and filter writers in their arms race beginning with the first spam in 1978. Listing the challenges encountered by both sides of the war makes it abundantly clear that filter writers currently have the upperhand and are widening their lead. To show this, he discusses techniques for obtaining valid test results and provides measures of accuracy for existing filters. Zdziarski uses these results to dispel various myths that keep users from better spam-filtering technology.

The real beauty of Ending Spam, though, is that it provides detailed explanations of filtering techniques without overwhelming or boring casual readers. For these people, short introductions to fundamental ideas such as Hidden Markov Models and Bayes' theorem are provided. Frequent examples help convey core concepts making up for the few instances where explanations are unclear. System administrators and filter authors should also find this book useful, as its explanation of what various features and settings of spam-filtering products can be helpful. Such readers may be particularly interested in string tokenization for language classification; filter training modes; training speed; obtaining good training corpora; and ensuring reasonable space and time efficiency on existing systems.

While many of the concepts covered in this book are not specific to spam filtering, additional challenges posed by spammers cause use of conventional implementations to fail. Zdziarski not only presents current approaches to overcoming spammer tactics used to evade each of the solutions mentioned, but also explains why such attempts ultimately fail. Lastly, he examines various spam-filtering packages currently available including his own, DSPAM, and lists the approaches employed by each. The all-encompassing nature of the book should therefore earn it a space on the shelf of anyone that wants to actively contribute to the reduction of spam.

—J.L.

Behind Closed Doors: Secrets of Great Management

Johanna Rothman and Esther Derby

The Pragmatic Programmers, 2005; 167 pp.; $24.95; ISBN 0976694026

One of the effects of the pending baby boom retirement cycle is going to be the exodus of an entire generation of management. A common solution to this problem in IT is to promote senior developers into management. A large percentage of these people likely had not given what it takes to be a manager much thought and being a good manager is, like a lot of things, a learned skill. Consequently, a lot of new managers face a steep learning curve upon elevation.

The premise of Johanna Rothman and Esther Derby's Behind Closed Doors: Secrets of Great Management is that a lot of the skills necessary to be a great manager are not readily observable but happen in private with their interactions between their staff and colleagues Behind Closed Doors. The book follows Sam, a manager recently brought into an organization, over a seven-week period in seven chapters; one per week. Each week has a broad goal to achieve such as "Learning about the People and Work" (week One) and "Managing Day to Day" (week Four). Within each chapter there are scenarios Sam encountered that week to achieve the week's goal. This structure is one of the stronger points of the book, as it transforms the narrative into a checklist for the reader's own managerial growth.

Another valuable item in the book in the series of short (most are only two pages) "Techniques for Practicing Great Management". These cover everything from coaching to running an effective meeting. These tips can be applied almost immediately and have a positive impact on an organization.

I enjoyed Behind Closed Doors and my copy has lots of notes in the margins of ways I can apply the content. While the content is geared towards the new or slightly experienced manager, I would recommend it even to those who have been doing it for a while due to the breadth and applicability of the topics covered.

—A.G.