Author: Dominik Spies

Into the Fire - A no less somewhat less nonsense introduction to NLP

Natural Language Processing? - What is NLP?

Language is messy. In our attempts to convey meaning, and emotions to each other, we have come up with some extraordinarily complex structures that need years of learning to grasp. There are countless rules and even more exceptions to those rules but somehow we manage to communicate with each other. The name, scientists have come up with for mess is natural language.

And then there are computers, machines that require a lot of structure to work. NLP is the attempt to make those two worlds meet, to have computers parse, process, and understand the language we use in our daily (natural) lifes. In the coming articles we will have a look at tools, techniques, and methods that help us deal with the chaotic complexity of natural language. We will see the many ways in which NLP will make dealing with language easier, one method at the time. Today we will start with the first:
Regular Expressions

Searching through a piece of text doesn’t sound like a task one would need a lot of fancy NLP technology for, but we recently had a case where this was actually necessary:

One of our customers asked us if we could help them with searching for specific terms in their documents. Their task was to deal with contracts and requirements, where missing even a small detail can potentially cost millions down the line. Additionally, these documents are usually very long, sometimes several thousands of pages. So if one where to simply Ctrl + F for a specific term one might get hundreds and hundreds of results, most of which irrelevant. 

Creating test cases by hand can be a lot of effort. It takes time, and so costs plenty of money. It is estimated that testing on average costs roughly 50% of the project budget.So maybe, we could try and skip it? Well, we still need to test and, among other things, make sure that the system behaves in the way we specified. But maybe we can develop an automatic method for creating tests? And this is the core idea: Why not use the specification to generate the tests?

Anyone who has used a recent version of Specmate might has already seen an amazing new feature. In the overview screen of any Cause-Effect-Graph is now an anoccurus little button titled “Generate Model”. Clicking this button will trigger a chain of systems, that is capable of using natural language processing to turn a sentence like

If the user has no login, and login is needed, or an error is detected, a warning window is shown and a signal is emitted.
directly into a CEG, without any additional work from the user: In this article we will do a deep dive into this feature, have a look at the natural language processing (NLP) pipeline required to make such a system work, see different approaches to implement it, and figure out how to garner the power of natural language processing for our goals.