Types of Research

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Types of Research

• Experimental
• Quasi-Experimental
• Descriptive Correlational
• Descriptive

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Experimental Research

• Establishes a cause and effect relationship.
• Allows generalization to a similar population.
• Employs an experimental group versus control
  group design determined by random assignment to
  the groups.

3
Quasi-Experimental Research

• Suggests a cause and effect relationship.
• Allows tentative generalization to a similar
  population.
• Employs an experimental group versus control
  group design with no random assignment to the
  groups or a pretest versus posttest design.

4
Descriptive Correlational Research

• Establishes the existence of a predictive
  relationship.
• Uses two or more sets of data to examine the
  existence and strength of a relationship between
  them.

5
Descriptive Research

• The researcher describes what exists.
• The researcher does not attempt to change the
  sample in any way.

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Educational Experimental or Quasi-Experimental
Research Design

• Determine the research problem or question.
• Compare the effects of an educational treatment
  (called the independent variable) on one or more
  groups.
• The independent variable or treatment is
  hypothesized to be the cause of any differences
  in the groups following treatment.

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Examples of Independent Variable(s) in Education

• Curriculum Whole language versus traditional
  curriculum
• Instruction Remedial intervention versus no
  intervention or remedial intervention pretest and
  posttest scores.

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Examples of Independent Variable(s) in Education

• Grouping Ability grouping versus no grouping or
  ability grouping versus cooperative grouping.
• Student Good readers versus poor readers or
  middle school students versus high school
  students.

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Dependent Variable(s) in Education

• What is measured in order to establish the effect
  of the treatment
• Involves numbers that can be submitted to
  statistical analysis

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Examples of Dependent Variables in Education

• Scores on standardized tests.
• Scores on researcher designed tests and/or
  rubrics.
• Scores on published informal instruments.

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Extraneous Variables

• Any factor that can cause an effect other than
  the independent variable
• Or
• Any factor that can prevent the effect of the
  independent variable

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Establishing Group Similarity

• Random assignment
• Similar sex
• Similar age
• Similar achievement levels
• Similar time constraints
• Other?

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Analyzing Group Differences

• Compare group scores ( group versus group or pre
  versus post) on dependent measures.
• Use a statistical formula to determine if scores
  are significantly different t-test, ANOVA.

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Generalize to Population

• If the treatment was effective with the chosen
  sample, it will probably have the same effect
  with a similar population.

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Descriptive Correlational Research

• Will be explained in detail in a later class.

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Descriptive Research Design

• Determine the research problem or question.
• Determine the sample.
• Determine the units of data analysis. (In order
  to use statistical formulas, these must be
  quantified in some way).

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Typical Ways to do Data Analysis

• Survey/questionnaire
• Observation
• Interview
• Audiotape or videotape
• Text book, student work, etc.
• Unit of data analysis/categories may emerge as
  the study is implemented.

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Method of Data Analysis

• To divide observations into categories of
  behavior (units of analysis
• Code and audio/videotape into categories of
  behavior
• Determine patterns of survey response
• Analyze interviews according to topics

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Analysis of Data

• May use statistical formulas if quantified.
• May involve narration.

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Action Research

• Can employ an experimental, quasi-experimental,
  descriptive correlational or descriptive design.
• Will probably involve a predetermined sample.
• Use of a predetermined sample limits generalizing
  beyond the population studied.