Constructing hypotheses & research design

The definition of a hypothesis A tentative proposition. Its validity is unknown. It specifies a relationship between two or more variables. An answer to a research question. It is not obligatory to have a hypothesis in a research but it is recommended.

Why it is needed? To bring direction, specificity & focus to a research study. To have something to test. The hypothesis can be proved to be: –right, –partly right, –wrong (false).

Functions of a hypothesis Providing focus What data to collect and what data not to collect Enhancing objectivity Making conclusions easier

Types of hypothesis Research hypothesis –Hypothesis of difference –Hypothesis of point-prevalence –Hypothesis of association Alternate hypothesis –Null hypothesis (H 0 )

Type I and type II errors in testing Type I error: accepting a false hypothesis Type II error: rejecting a hypothesis that is true

Research design Plan + Structure + Strategy of investigation to obtain answers to research questions or problems. How the full research is to be completed? (operationalizing the variables, selecting the sample, data collection etc.)

Functions of research design Conceptualise an operational plan to undertake the various procedures and tasks Ensure that the procedures will obtain valid, objective and accurate answers to teh research question.