A research hypothesis can be defined as a presumption made by a researcher about an experiment. It is from a research hypothesis that theories are generated. I intend to analyze the various types of hypotheses, show you why a null hypothesis is distinct from a research hypothesis, explain the difference between a non-directional research and a directional research hypothesis and we will thereafter look at the characteristics of a good research hypothesis.
There are several types of hypotheses. Basically, there are two broad types; a research hypothesis and an alternate hypothesis. A research hypothesis can be further classified, based upon the way it is formulated, as a null hypothesis, a hypothesis of difference, a hypothesis of point-prevalence and a hypothesis of association. A research hypothesis can also be classified as either non-directional or directional (Kumar, 2005 79)
The main distinction between a null hypothesis and a research hypothesis is that while a null hypothesis shows no correlation between two things or the items in discussion, a research hypothesis on the other hand, clearly shows their connection.
A researcher for instance, investigating the link between wealth and happiness in a marriage relationship may formulate both a null hypothesis and a research hypothesis. The null hypothesis may read: a lot of wealth and just enough wealth are rated the same in happiness by couples. The research hypothesis: a lot of wealth is rated by couples as bringing more happiness than just enough wealth. It is important to note that a null hypothesis should be the exact opposite of a research hypothesis.
When classifying a research hypothesis as either non-directional or directional, this is normally done on the basis of precision. Whereas one (non-directional hypothesis) only indicates that one thing differs from another at some point, a directional hypothesis specifies the type of the difference. In simple terms, a non-directional hypothesis is general but a directional hypothesis is specific.
So that one can specifically conclude what is true or false so as to formulate a theory, a good research hypothesis has several characteristics. Key among them is that the hypothesis must be easy to test. For one to achieve this, you need to be familiar with the subject area. “The more insight you have into a problem, the easier it is to construct a hypothesis.” (Kumar, 75)
Secondly, a good research hypothesis should be capable of verification. That is, methods and techniques must be available for date collection and analysis. This should not, however, discourage anyone from formulating a hypothesis, for while doing your research; you may come up with new techniques to verify it.
Another point of great importance is that hypothesis should be related to the existing body of knowledge. A research’s main purpose is that a hypothesis should not only emerge from the existing body of knowledge, but it should also add to it.
Last but not least, a hypothesis should be operational .That is, it can be expressed in terms that can be measured. As the rule goes, if it cannot be measured, it cannot be tested and, hence, no conclusions can be drawn (Kumar, 76),
It is interesting to note that hypotheses are not only used by researchers. We all constantly make them in our minds in our bid to understand day-to-day occurrences.
Although a perfectly valid study can be conducted without constructing a single research hypothesis, hypotheses are important for bringing clarity, specificity and focus to a research study.
Kumar R. Research Methodology: A Step-by-step Guide for Beginners.