Ed 603 - Lesson 6 - Formulation and Statement of a Research Hypothesis

Lesson 6 will consist of the following topics

· Text Assignment for Lesson 6

· What is a research hypothesis?

· Formulating a research hypothesis

· Formulating research hypotheses for various types of research problems

· Lesson 6 Assignment

· Lesson 6 Quiz

Text Assignment for Lesson 6

For lesson 6, read pages 62-67 in Educational Research: Competencies for Analysis and Application, Seventh Edition by L. R. Gay and Peter Airasian (2003, Merrill/Prentice Hall, ISBN 0-13-099463-4)

or read pages 56-62 in Educational Research: Competencies for Analysis and Application, Eighth Edition by Lorrie Gay, Geoffrey Mills, and Peter Airasian (2006, Prentice-Hall, ISBN 0-13-118534-9)

or read pages 120-149 in Educational Research: Planning, Conducting, and Evaluating Quantitative and Qualitative Research, 3^rd Edition by John W. Creswell (2008, Merrill/Prentice Hall, ISBN-13: 978-0-13-613550-0)

What is a research hypothesis?

According to Gay (1996, page 61), a hypothesis is a tentative explanation for certain behaviors, phenomena, or events that have occurred or will occur.

1. The hypothesis states the researcher's expectations concerning the relationship between the variables in the research problem.

2. The hypothesis is a refinement of the research problem. It is the most specific statement of the problem.

3. The hypothesis states what the researcher thinks the outcome of the study will be.

4. The researcher collects data that either supports the hypothesis or does not support it.

5. The hypothesis is formulated following the review of related literature and prior to the execution of the study. The related literature leads the researcher to expect a certain relationship.

6. "A good hypothesis states as clearly and concisely as possible the expected relationship (or differencce) between two variables and defines those variables in operational, measurable terms." (Gay 1996, page 62).

7. "A well-stated and defined hypothesis must be (and will be if well-formulated and stated) testable. It should be possible to support or not support the hypothesis by collecting and analyzing data." (Gay, 1996, page 62).

Formulating a research hypothesis

To formulate a research hypothesis we start with a research question and:

8. generate operational definitions for all variables, and

9. formulate a research hypothesis keeping in mind

§ expected relationships or differences

§ operational definitions

10. Hypothesis can also be classified in terms of how they were derived

§ inductive hypothesis - a generalization based on observation

§ deductive hypothesses - derived from theory

11. A hypothesis can be directional or non-directional.

12. Hypotheses can also be stated as research hypotheses (as we have considered them so far) or as statistical hypotheses.

13. The statistical hypotheses consist of the null hypothesis (H₀), the hypothesis of no difference and the alternative hypothesis (H₁ or H_A) which is similar in form to the research hypothesis.

Formulating research hypotheses for various types of research problems

Let's consider a model or formula for stating a research hypothesis for each of the types of quantitative research types we have looked at in earlier lessons.

14. A model for stating hypotheses for an experimental or causal-comparative study.

If X is the independent variable, Y is the dependent variable, and S is the Subject, we can state our research hypothesis as Ss who get X do better on Y than subjects who do not get X (or get some other X).

Here is an example: In our study we will hypothesize that first grade girls will show better reading comprehension than first grade boys. Now lets state that as a research hypothesis. It would be a causal-comparative research study.

Research Hypothesis: Girls will achieve higher reading comprehension test scores than boys at the end of the first grade.

Operational Variables: Reading comprehension will be measured by the Iowa Tests of Educational Development, Reading Comprehension, administered at the end of the year.

Statistical Hypotheses: When we get ready to analyze our data we might also wish to state statistical hypotheses for our problem. The statistical hypotheses consist of the null hypothesis (H₀) and the alternative hypothesis (H₁). If we let stand for the mean of the girls and stand for the mean of the boys, our null and alternative hypotheses would be:

In other words the null hypothesis states that there is no difference between the two means on the reading comprehension test scores, while the alternative hypothesis states that the girls mean score on the reading comprehension test will significantly exceed that of the boys. Generally we use a statistical test (e.g. the t-test) to decide if the girls score significantly higher than the boys. We will discuss statistical hypotheses and the use of inferential statistics in lessons 9 through 13 when we look at the design, proceedures, and data analysis for each of the types of quantitative research types.

15. A model for stating hypotheses for correlational research.

If A and B are variables (note that we do not refer to them as independent and dependent variables in correlational research), and C is the subject we can state our research problem as the relationship between A and B for C. (What is the relationship between A and B for C)

We can state our research hypothesis as - There will be a significant positive correlation between A and B for C (or significant negative relationship or significant relationship without specifying direction). We will also need to provide operational definitions for A and B and describe C.

Lets analyze the following research example and indicate the research hypotheses.

An instructor investigates the relationship between the number of minutes needed to complete an examination and the score on the examination. He wants to use the data to determine whether there is a significant negative relationship between these two variables.

Research Hypothesis: The length of time needed to complete an examination will be negatively correlated with the score on the examination for college students.

Statistical Hypotheses:

16. Applying the model to desciptive research.

If A, B, C, and D are variables, and E is the subject or subject group, we can state the research problem as follows:

Research Problem: A, B, C, and D among E (How can E be described in terms of A, B, C, and D?). We will need operational definitions for A, B, C, and D and will need to describe E.

Research Hypothesis: There is no specified relationship between the variables thus no research hypothesis. There is a research problem but not a formal research hypothesis.

Example: A researcher wants to find out the educational characteristics of gifted students with learning disabilities in the middle school. When asked what is meant by "educational characteristics" the researcher lists the following variables - IQ, reading achievement, mathamatics achievement, written language achievement, and locus of control (internal versus external locus of control).

Research Question: What is the average level of IQ, reading comprehension, mathematics performance, written language proficiency, and locus of control for gifted children with learning disabilities in the middle school.

Operational Definitions:

1. IQ - Scores on an individually administered IQ test

2. Reading Comprehension - Scores on the Woodcock Reading Mastery Tests

3. Mathematics Performance - Scores on the Woodcock Johnson Tests of Achievement: Mathematics Section

4. Written Language Proficiency - Scores on the Woodcock Johnson Tests of Achievement: Written Language Section

5. Locus of Control - A suitable measure for internal versus external locus of control will be selected

In the assignment for this lesson you will have an opportunity to look at some research topics and formulate research hypotheses and operational definitions of variables.