Jeff Jackson's Research Interests

Much of my research has been involved one way or another with questions about automatically learning DNF expressions from examples. A DNF expression is an OR of AND's of boolean expressions (DNF stands for "Disjunctive Normal Form"). Expressed in English, a DNF looks something like the condition of the following if-then:

 if
it is raining
OR
the forecast calls for rain
AND
you trust weather forecasts
OR
you like to always be prepared
AND
you are taking a briefcase
AND
your briefcase is not full
then
take an umbrella when you go out.

DNF expressions are particularly interesting to machine learning researchers because DNF is a natural means of representing many "expert" rules, like the one above. Furthermore, in very practical areas such as digital circuit design and implementation DNF expressions are used extensively, typically under a different name such as sum-of-products notation. So improving our understanding of DNF expressions themselves as well as methods for acquiring them from data in an automated fashion seems a potentially valuable enterprise.

My major result to date is an algorithm for efficiently learning DNF expressions in a specific (interesting) learning model. On the flip side, I also contributed to a paper that shows that DNF is probably not learnable in a more realistic model of learning. While this work has not fully resolved the DNF learnability questions, it has taken us well beyond where we were prior to this work.

In addition to this theoretical research, I have also been involved in developing and testing new applied machine learning algorithms. My approach has been to take what seem to be especially insightful ideas from theory and look for ways to incorporate them in practice. This also feeds back new questions for theoretical consideration.

I have also taken several side trips that have produced some interesting results. I developed--and with a Nasa researcher tested with human subjects--an automated gesture recognition system. I also contributed to a nice comparative study of the impact that object-oriented software design has on development productivity. Even my eight years spent as a software engineer and manager led to the publication of a "lessons-learned" paper. A more-or-less complete list of my conference and journal publications can be found below; several are on-line, and I can email copies of most others on request.

One other major "research" side trip involved writing my textbook, Web Technologies: A Computer Science Perspective. While this book is not related to my scientific research publications list below, it did involve a tremendous amount of time spent researching (in the college term paper sense) web references.

Some links to other information about me and some of what I'm involved in:

Papers

E-mail: Please search for my name at http://www2.duq.edu/locator/directory.cfm.