a Specifying Purpose, Research Questions or Hypothesis
Educational Research by John W. Creswell. Copyright 2002 by Pearson Education. All rights reserved.
Slide 1
Key Ideas
The difference between purpose statements, hypotheses, and research questions Variables in quantitative research Qualitative research considerations
Educational Research by John W. Creswell. Copyright 2002 by Pearson Education. All rights reserved.
Slide 2
Purpose Statements, Research Questions, Research Hypotheses, Research Objectives Purpose statements: a declarative statement that advances the overall direction or focus for the study. Research Questions: Interrogative statements that narrow the purpose statement to specific questions that researchers seek to answer in their study.
Educational Research by John W. Creswell. Copyright 2002 by Pearson Education. All rights reserved.
Slide 3
Purpose Statements, Research Questions, Research Hypotheses, Research Objectives Research Hypotheses: Declarative statements in quantitative research in which the investigator makes a prediction or conjecture about the outcomes relationship. Research Objective: A statement of intent for the study that specifies specific goals that the investigator plans to achieve in a study.
Educational Research by John W. Creswell. Copyright 2002 by Pearson Education. All rights reserved.
Slide 4
Distinguishing among various forms of direction in research
Purpose Statement Intent Form Use
Overall Direction
Research Questions
Raise questions to be answered One or more questions
Hypothesis
Make predictions about expectations One or more questions
Research Objectives
State Goals One or More Objectives
One or more
sentences Quantitative and Qualitative Research End of Introduction
Placement
Educational Research by John W. Creswell. Copyright 2002 by Pearson Education. All rights reserved.
Quantitative Quantitative Typically and Research Quantitative Qualitative Research Research End of the introduction, after the literature review, or in a separate section of the study
Slide 5
Stating Hypotheses
Quantitative hypotheses
A researchers tentative prediction of the results of the research Formulated on the basis of knowledge of the underlying theory or implications from the literature review Testing hypotheses leads to support or lack thereof
Educational Research by John W. Creswell. Copyright 2002 by Pearson Education. All rights reserved.
Slide 6
Stating Hypotheses
A good hypothesis
is based on sound reasoning. provides a reasonable explanation for the predicted outcome. clearly and concisely states the expected relationships between variables. is testable.
Educational Research by John W. Creswell. Copyright 2002 by Pearson Education. All rights reserved.
Slide 7
Stating Hypotheses
Types of hypotheses
Inductive a generalization made from a number of observations Deductive derived from theory and aimed at providing evidence to support, expand, or contradict aspects of that theory
Educational Research by John W. Creswell. Copyright 2002 by Pearson Education. All rights reserved.
Slide 8
Stating Hypotheses
Types of hypotheses (continued)
Research hypotheses state the expected relationship between two variables
Non-directional a statement that a relationship or difference exists between the variables Directional a statement of the expected direction of the relationship or difference between variables Null a statement that no statistically significant relationship of difference exists between variable
Educational Research by John W. Creswell. Copyright 2002 by Pearson Education. All rights reserved.
Slide 9
Stating Hypotheses
Qualitative hypotheses
Given the nature of qualitative research, formal a-priori hypotheses are not stated
Generating role of qualitative research Testing role of quantitative research
Focus is on generating new hypotheses as a result of the study (i.e., inductive hypotheses)
Educational Research by John W. Creswell. Copyright 2002 by Pearson Education. All rights reserved.
Slide 10
Stating Hypotheses
Formats for experimental studies
P who get X do better on Y that P who do not get X
P represents the participant X represents the treatment Y represents the outcome
Testing hypotheses
Statistical analysis of data Importance of the results regardless of the outcome
Educational Research by John W. Creswell. Copyright 2002 by Pearson Education. All rights reserved.
Slide 11
Definition of a Variable
A Variable (A Characteristic or Attribute)
Can be Measured
(Can be assessed on an instrument and recorded on an instrument)
and
(Can assume different values or scores for different individuals)
Slide 12
Varies
Educational Research by John W. Creswell. Copyright 2002 by Pearson Education. All rights reserved.
Variables and Constructs
A Variable is an attribute or characteristic stated in a specific or applied way A Construct is an attribute or characteristic expressed in an abstract, general way.
Construct Variable Student Achievement Grade Point Average
Educational Research by John W. Creswell. Copyright 2002 by Pearson Education. All rights reserved.
Slide 13
Categorical and Continuous Scores
A categorical score is a value of a variable assigned by the researcher into a small number of categories. (e.g. Gender) A continuous variable is the value of a variable assigned by the researcher to a point along a continuum of scores, from low to high. (e.g. Age)
Educational Research by John W. Copyright Creswell. 2002 by Pearson Education. All rights reserved.
Slide 14
Families of Variables
Independent Variable: An attribute or characteristic that influences or effects an outcome of the independent variable.
Treatment Variable Measured Variable Control Variables Moderating Variables
Educational Research by John W. Creswell. Copyright 2002 by Pearson Education. All rights reserved.
Slide 15
Families of Variables
Intervening Variables (Mediating Variables): An attribute or characteristic that stands between the dependent and independent variables. Dependent Variables: An attribute or characteristic influenced by the independent variable.
Educational Research by John W. Creswell. Copyright 2002 by Pearson Education. All rights reserved.
Slide 16
Families of Variables
Confounding Variables (Spurious Variables): Attributes or characteristics that the researcher cannot directly measure because their effects cannot be easily separated from the other variables, even though they may influence the relationship between the independent and the independent variable.
Educational Research by John W. Creswell. Copyright 2002 by Pearson Education. All rights reserved.
Slide 17
The Family of Variables in Quantitative Studies
Probable Cause
Independent Variables Treatment Measured Control Variables Moderating Variables
Educational Research by John W. Creswell. Copyright 2002 by Pearson Education. All rights reserved.
Effect
Intervening Variables Dependent Variables
Confounding Variables
Slide 18
Intervening Variables Stand Between Independent and Dependent Variables
Step 1
Independent Variable
for students
Dependent Variable
Student seeks help from faculty
Example Convenient office hours
Step 2
Example
Independent Variable Variable
Convenient office hours for students
Intervening Variable
Student becomes willing to take risks
Step 3
Example
Independent Variable
Convenient office hours for students
Intervening Variable
Student becomes willing to take risks
Dependent Variable
Student seeks help from faculty
Slide 19
Educational Research by John W. Creswell. Copyright 2002 by Pearson Education. All rights reserved.
Theories as Bridges Between Independent and Dependent Variables
Independent Variables
Dependent Variables
Educational Research by John W. Creswell. Copyright 2002 by Pearson Education. All rights reserved.
Slide 20
Extensive Tests by other researchers
Different Types of Explanations in Quantitative Research
As a formal theory that is expressed by connected hypotheses and variables identified by authors As a conceptual framework often expressed as a visual model by other authors for relationship As a theoretical rationale posed by other authors based on studies for relationship
Broad Abstractions
No Test
As explanation posed by the author as a hunch for why the independent variable relates to the dependent variable
Narrow Application
Slide 21
Educational Research by John W. Creswell. Copyright 2002 by Pearson Education. All rights reserved.
Whether Variables Prove Probable Cause
Probable causation: The researchers attempt to establish a likely cause/effect relationship between variables rather than prove the relationship. Control is vital: Control means that the researcher attempts to study all fact...