Providing a Free Web Service:
How to Do It and Why

Gary Perlman

Document: freeweb.html 2000-12-15
Presented 1998-10-13 to ACM BuckCHI

Table of Contents


These days, if you're not on the Web, you don't exist. While you're putting up your Web site, you might consider what you can offer people to make them come to your site and what can be gained by offering a free service as part of your site.

The HCI Bibliography (HCIBIB) is a free-access online bibliography on Human-Computer Interaction. It has over 18,000 entries, most with abstracts, and with over 4000 links to full text. It is browsable and searchable from its web site: This presentation will cover:

If there is time and interest, we will cover the construction of some parts of the site using perl, CGI, and SSI (server-side includes).

HCI Bibliography as a Resource for Practitioners

Contents of the Database 18K Records

The HCI Bibliography is the largest free-access online bibliography on Human-Computer Interaction. It includes entries on most major conferences, journals, and books in the field.

Project is Budget-Free

The HCI Bibliography is a free service (although its materials are copyrighted). To be a free service, publishers, volunteers, and organizations have contributed.

Data Accessed on Web, via FTP

The HCI Bibliography has its own domain on the Internet and allows both Web and FTP access.

Web Site Features Overviews of Data

Special files have been generated from databases about journals, conferences, and books, to provide various views of the structure of the database.

Link Indexes Generated from Internet Resources

In 1998, the HCI Bibliography began cataloging Internet resources and now describes over 800. SIGCHI and SIGCAPH indexes, (with links to forms to suggest new resources).

HCIBIB Search Service

The HCI Bibliography search service allows users around the world to find records via a Web form.

Design and Maintenance of the Website

The HCI Bibliography began as an FTP site with an email file delivery service but is now primarily a Web site with FTP access.

Original Site @

New Site @

Site Redesign April 1998

Typical Update to the Site

Getting high-quality bibliographic records online has always been the primary focus of the Project. The HCI Bibliography procedures are summarized below.
  1. new "module": conference proceedings / journal volume
  2. obtain copy of module by:
  3. get module online
  4. data quality control
    1. insertion of representative "bugs" into file
    2. volunteer validation via email
    3. calculate validator error detection rate
    4. estimate number of remaining errors in file
    5. release data (through filter) if "correct enough"
    6. update database
  5. Update of Site (1-5 minutes)

Search Service Started April 1998

Evaluation of the HCIBIB Search Service

It's ironic that the HCI Bibliography should have a search service that is anything but usable, but the constraints of budget and availability of software has resulted in some compromises. This makes for some interesting observation of system usage, and some opportunities to evaluate ways to make the system more usable.

Expert System for Feedback

Users do not plan searches, so an expert system provides feedback.

Making Users Use Feedback

Users do not make good use of feedback.

Most Used/Effective Features

Coolest Features

Features Under Consideration

Example Analysis of Logged Data

Most interesting analysis is informal, of "sessions".
Schneiderman visualisation -i DATA    FMT FULL
	Ben's last name spelled incorrectly
Shneiderman visualisation  -i DATA    FMT FULL
	terms need not be adjacent
Shneiderman;visualisation  -i DATA    FMT FULL
	British spelling did not match
Shneiderman;visualization  -i DATA    FMT FULL
	highlight the terms
Shneiderman;visualization  -i DATA    FMT FULL HIGHLIGHT
	show top terms
Shneiderman;visualization  -i SUMMARY FMT FULL TOKENS HIGHLIGHT
New initiative: Ask an Expert

Benefits from Offering a Free Web Service

Why Work on the HCIBIB?

  1. sublimates obvious compulsive disorder
  2. satisfaction of helping a worthwhile community
  3. work has lasting value (once online, forever online)

Why Offer a Free Web Service?

  1. a laboratory for evaluating ideas
  2. learn new ways to implement new ideas
  3. monitor how features are used, how often
  4. gather ideas, skills, tools for use in "real" website/service (EXAMPLE, SOURCE)
  5. a place to advertise other goods & services
  6. positive perception from user community (altruism / expertise)

Few Reasons Why Not

What free service can you provide?

Bonus Tutorial Section

Flexible/Consistent Page Design with Server-Side Includes

Efficient, Reliable, and Informative Web Counters

Activity Report:   today   yesterday   day before yesterday
#! /usr/local/bin/perl

# Usage: file
# Result: appends day of week to file and reports the size
# Init:   must create world-writeable file initially
#         insert in file <!--#exec cmd=" counter-file" -->

$count_file = $ARGV[0];
local ($sec,$min,$hour,$mday,$mon,$year,$wday,$yday,$isdst) = localtime;

if (open (FILE, ">>$count_file")) { # appends to file, so no lock needed
	print FILE $wday; # uses day of week for daily counts
	close (FILE);

local ($dev,$ino,$mode,$nlink,$uid,$gid,$rdev,$size,$atime,$mtime,$ctime,$blksize,$blocks) = stat ($count_file);

print "$size"; # report file size (== visits) to caller

exit (0);

Maintaining State in Forms

  1. read default data
  2. read form data (override default data)
  3. display screen using current state (hidden) in form