Do we need research questions and hypotheses in our research? Does writing a research question exempt us from going further with hypotheses building? Are there different types of hypotheses? How to develop them?
Write research questions and hypotheses
After stating your research purpose, you should narrow the focus of your study through specific questions to be answered or hypotheses to be tested.
Research questions can be defined as ‘questions in quantitative or qualitative research that narrow the purpose statement to specific questions that researchers seek to answer’.
Hypotheses are ‘statements in quantitative research in which the investigator makes a prediction or a conjecture about the outcome of a relationship among attributes or characteristics’.
Qualitative research questions
In a qualitative study, researchers develop research questions, not objectives (i.e., specific goals for the research) or hypotheses (i.e., predictions to be tested). These research questions adopt two forms: a central question and associated sub questions.
How to write good qualitative research questions?
To write good qualitative research questions, consider the followings:
- Ask one or two central questions followed by five to seven subquestions.
- Start your research questions with the words “what” or “how” to express an open and emerging design.
- Focus on a single phenomenon or concept.
- Use exploratory verbs that express the language of emerging design of research, e.g., discover, seek to understand, explore a process, describe the experiences, and report the stories.
- Avoid directional words that suggest or infer a quantitative study, e.g., affect, influence, impact, determine, cause, and relate.
- Expect your research questions to be evolved during your study.
Examples for qualitative research questions
- How do early adolescent females read literature that falls outside the realm of fictions?
- (a) How do women in a psychology doctoral program describe their decision to return to school? (b) How do women in a psychology doctoral program describe school change these women’s lives?
Quantitative research questions and hypotheses
In your quantitative study, use research questions and(or) hypotheses to shape and specifically focus the purpose of the study. Research hypotheses are numeric estimates of population values based on data collected from samples. Hypotheses are tested through statistical procedures in which inferences are drawn about the population from the study sample.
How to write good quantitative research questions and hypotheses?
To write good quantitative research questions and hypotheses, consider the followings:
- Develop either research questions or hypotheses to reduce redundancy.
- Include your variables in your questions and hypotheses in three basic manners:
- Describing responses to the independent, mediating, or dependent variables.
- Comparing groups on an independent variable to see its impact on a dependent variable.
- Relating one or more independent variables to a dependent variable.
- Use the same pattern of word order in the questions or hypotheses to help a reader to easily identify your major variables.
- Develop your research questions and hypotheses based on a theory.
- Measure your independent and dependent variables separately. This process supports the cause and effect logic of quantitative research.
- If hypotheses are used, there are two basic forms:
- A null hypothesis, which makes a prediction that in the general population, no relationship or no difference exists between groups on a variable.
- The alternative hypothesis. The investigator makes a prediction about the expected result for the population of the study. These predictions comes from relevant literature and may be: directional (e.g., ‘higher’, ‘lower’, ‘more’, or ‘less’) and nondirectional (“There is a difference” between).
- If questions are used, there are two basic forms:
- Descriptive questions that describe each independent and dependent variable.
- Inferential questions that relate variables or compare groups, following these descriptive questions.
Examples for null, directional, and nondirectional hypotheses
- There is no significant difference between the effects of verbal cues, rewards, and no reinforcement in terms of social interaction for children with autism and their siblings (null hypothesis).
- Gender identity of religious and secular Arab and Jewish women are related to different sociopolitical social orders that reflect the different value systems they embrace (nondirectional hypotheses).
- Religious women with salient gender identity are less socio-politically active than secular women with salient gender identities (directional hypotheses).
- The relationships among gender identity, religiosity, and social actions are weaker among Arab women than among Jewish women (directional hypotheses).
Examples for descriptive and inferential questions
- How do the students rate on critical thinking skills? (A descriptive question focused on the independent variable)
- What are the students’ achievement levels (or grades) in science classes? (A descriptive question focused on the dependent variable)
- What are the student’s prior grades in science classes? (A descriptive question focused on the control variable of prior grades).
- What is the educational attainment of the parents of the eight- graders? (A descriptive question focused on another control variable, educational attainment of parents).
- Does critical thinking ability relate to student achievement? (An inferential question relating the independent and the dependent variables)
- Does critical thinking ability relate to student achievement, controlling or the effects of prior grades in science and the educational attainment of the eight-graders’ parents? (An inferential question relating the independent and the dependent variables, controlling for the effects of the two controlled variables).
Creswell, J.W. (2012). Educational Research: Planning, Conducting, and Evaluating Quantitative and Qualitative Research, 4th ed. Boston, MA: Pearson Education.
Creswell, J.W. (2003). Research Design: Qualitative, Quantitative, and Mixed Methods Approaches, 2nd ed. Thousand Oaks, California: Sage Publications.