Parush, A. (2006): Bridge the gap: Toward a common ground: practice and research in HCI, interactionsVolume 13, Number 6 (2006), Pages 61-62.
This article addresses an important question: the one of the linkage between the study of behavioral, social, organizational, and other phenomena associated with interactive computing systems and design, evaluation, and/or implementation of such systems:
Imagine you are a practitioner asked to examine an application. If you find it ineffective, you'll need to propose what needs to be redesigned in the user interface to improve its effectiveness. You are then faced with the question of why it is ineffective. In other words, you have a question that requires relevant research findings that can inform you of why or why not things work in your application. Such understanding can drive better design decisions. (...) The ability to utilize and benefit from any of the research types depends on how a practitioner defines his practical problem as a research question. The abstraction of the question on different levels can lead one to search and find potentially beneficial research that can be applied in the practical arena.
In this context, the author defines research as "any systematic endeavor to find an answer to a practical or theoretical question" and he distinguished 4 tiers in HCI research: usability, comparison, guidelines and theory. These dimensions differs according to the "level of focus" ("ange from addressing questions focusing on a specific product, to comparing between products, to searching and examining guidelines for a family of products, through to general questions on behavioral, social, organizational, and other phenomena") and "extent of generalization". Depending on the research questions, various methodologies can be applied (and sometimes there is no need to further generalizations).
Research questions hence range from "Does this product work for the user?" to "Why does it work?". This relates to Jarvinen's taxonomy of research (that I blogged here) Why do I blog this? because that's a very recurrent problem in my field. My stance on this is to say that research (for instance the one I do for my phd work) aimed at giving insights to designers and providing concepts and tools to analyze existing systems.