From helping to assess the value of new medical treatments to evaluating the
factors that affect our opinions and behaviors, analysts today are finding
myriad uses for categorical data methods. In this book we introduce these
methods and the theory behind them.
Statistical methods for categorical responses were late in gaining the level
of sophistication achieved early in the twentieth Century by methods for
continuous responses. Despite influential work around 1900 by the British
statistician Karl Pearson, relatively little development of models for categorical
responses occurred until the 1960s. In this book we describe the early
fundamental work that still has importance today but place primary emphasis
on more recent modeling approaches. Before outlining
The literature of cryptography has a curious history. Secrecy, of course, has always played a central
role, but until the First World War, important developments appeared in print in a more or less
timely fashion and the field moved forward in much the same way as other specialized disciplines.
As late as 1918, one of the most influential cryptanalytic papers of the twentieth Century, William F.
Friedman’s monograph The Index of Coincidence and Its Applications in Cryptography, appeared as
a research report of the private Riverbank Laboratories [577]. And this, despite the fact that the work
had been done as part of the war effort. In the same year Edward H. Hebern of Oakland, California
filed the first patent for a rotor machine [710], the device destined to be a mainstay of military
cryptography for nearly 50 years.
CDMA has been quite successful as a second-generation cellular system,having achieved widespread use in particular in North America and Korea by the turn of the twenty-first Century.
The software and hardware development fields evolved along separate paths through the end of the 20th Century. We seem to have come full circle, however. The previously rigid hardware on which our programs run is softening in many ways. Embedded systems are largely responsible for this softening. These hidden computing systems drive the electronic products around us, including consumer products like digital cameras and personal digital assistants, office automation equipment like copy machines and printers, medical devices like heart monitors and ventilators, and automotive electronics like cruise controls and antilock brakes.
Embedded systems force designers to work under incredibly tight time-tomarket, power consumption, size, performance, flexibility, and cost constraints.
Many technologies introduced over the past two decades have sought to help satisfy these constraints. To understand these technologies, it is important to first distinguish the underlying embedded systems elements.
Since the telephone was invented in the late nineteenth Century, there has been a
steady development of telephone services, and the number of subscribers has con-
tinuously increased. One of the most revolutionary developments in telephone serv-
ice in the late twentieth Century was the introduction of the cellular variety of
mobile phone services.
The capability of radio waves to provide almost instantaneous distant communications
without interconnecting wires was a major factor in the explosive growth of communica-
tions during the 20th Century. With the dawn of the 21st Century, the future for communi-
cations systems seems limitless. The invention of the vacuum tube made radio a practical
and affordable communications medium.
When the authors of this book asked me to write the foreword of
their work on the digital enterprise, I immediately thought that it was
one more document on a fashionable topic in the technology and the
business world of the 21st Century often addressed by consulting
firms, some of which have aspired to become experts on the subject.
However, a more careful observation reveals that an issue more
important than the sole subject of the digital enterprise is: “Is your
company fully operational?”, because this is the real topic.
The information technology (IT) revolution is surely coming in this Century, just
as did the agricultural and industrial revolutions that have already so enriched our
lives. As the IT revolution progresses, it is expected that almost all social struc-
tures and economic activities will be changed substantially
