Week 10 Power Point (Research Methods)

• Research Designs


  • Nonexperimental
  • Quasi-Experimental
  • Experimental
• Nonexperimental design


  Makes little or no attempt to minimize threats to internal validity
• Quasi-experimental design


  Makes some attempt to minimize threats to internal validity—is almost, but not quite, a true experiment
• Research Designs


  • Experimental
  • Quasi-Experimental
  • Non-Experimental
• Experimental


  • Randomized Sample (Every individual who entered your study had an equal chance of being part of the treatment condition)
  • Control group
• Quasi-Experimental


  • Not randomized/ partially randomized
  • No control group
• Non-Experimental


  • Convenience, matched pair, quota sampling, cluster sampling, stratified random sampling
  • No intervention
• Nonexperimental research design


  A research strategy that attempts to demonstrate a relationship between two variables by comparing different groups of scores but makes no attempt to minimize threats to internal validity or to explain the relationship
• Nonexperimental Research Strategies


  • Differential Design
  • Interrupted Time Series
  • Nonexperimental Pretest-Posttest Design (Within)
• Differential Research Design


  Study which compares pre-existing groups. Groups already exist (gender, race, personality, existence of health issue). A dependent variable is then measured for each participant.
• Nonexperimental Pretest-Posttest Design (Within)

  Each individual in a single group of participants is measured once before treatment and once after treatment. Within the nonexperimental group you are not providing the treatment.
• Correlational


  A researcher measures the two Variables of interest with little or no attempt to control extraneous variables and then assesses the relationship between them.
• Goal of correlational research strategy

  To establish that a relationship exists between variables and to describe the nature of the relationship. Relationships can be described—not explained. There is no attempt to manipulate, control, or interfere with the variables.
• Scatter Plot Data from a Correlational Study

  Scores in each pair are identified as X and Y. Data can be presented in a list showing the two scores for each individual. Scores can be shown in a scatter plot graph, with each individual's score shown as a single dot with a horizontal coordinate (X) and a vertical coordinate (Y).
• Correlation Coefficient


  Measures and describes the relationship between two variables. It describes three characteristics of a relationship: Direction, Form, Consistency or strength.
• Direction of the Relationship

  Positive relationship: two variables change in the same direction. Negative relationship: two variables change in opposite directions.
• Form of the Relationship

  Linear relationship: the data points in the scatter plot tend to cluster around a straight line. Positive linear relationship: each time the X variable increases by 1 point, the Y variable increases in a consistently predictable amount.
• Consistency or Strength of the Relationship

  Correlation (correlation coefficient): measures and describes the relationship between two variables. The sign (+/–) indicates the direction of the relationship. The numerical value (0 to 1.0) indicates the strength or consistency of the relationship.
• Correlation does not imply causation
• Applications of the Correlational Strategy

  Predicting one variable from another. A correlational study demonstrating a relationship between two variables allows researchers to use knowledge about one variable to help predict or explain the second variable (SAT, grades). Predictor variable: the first variable. Criterion variable: the second variable (being explained or predicted).
• Strengths of the Correlational Research Strategy

  • Describes relationships between variables
  • Nonintrusive—natural behaviours
  • High external validity
  • Data can be taken during naturalistic observation and also researcher may use of archival data which were already collected for some other purpose
• Weaknesses of the Correlational Research Strategy

  • Cannot assess causality
  • Third-variable problem
  • Directionality problem
  • Low internal validity
• Third-variable problem


  Because two variables are related, does not mean that there must be a direct relationship between the two variables. A third (unidentified) variable may be responsible for producing the observed relation.
• Directionality problem

  A correlational study does not establish a relationship of cause-and-effect. Which is the cause / which is the effect.
• Types of Qualitative Research

  • Case studies
  • Naturalistic observations
  • Surveys
• Qualitative Research


  Involves asking broader research questions, interviews and observations that are summarized and interpreted in a narrative report using non-statistical analysis. Helps to generate new and interesting research questions and hypotheses.
• Qualitative Data Collection Methods

  • Interviews (unstructured, open ended)
  • Focus groups
  • Participant observations
• Grounded Theory in Qualitative Analysis


  Researchers start with the data and develop a theory or an interpretation that is "grounded in" those data. Identify ideas that are repeated throughout the data. Organize these ideas into a smaller number of broader themes. Write a theoretical narrative—an interpretation—of the data.
• Thematic analysis


  Themes that emerge in the data
• Conversation analysis


  The way the words were said in an interview or focus group
• Data Collection


  • Interviews (unstructured, open ended)
  • Focus groups
  • Participant observations
• Using Grounded Theory in Qualitative Analysis


  1. Researchers start with the data and develop a theory or an interpretation that is "grounded in" those data

  2. Identify ideas that are repeated throughout the data

  3. Organize these ideas into a smaller number of broader themes

  4. Write a theoretical narrative—an interpretation—of the data
• Thematic Analysis


  • Table 7.1 Themes and Repeating Ideas in a Study of Postpartum Depression Among Low-Income Mothers
• Theme


  • Ambivalence
  • Caregiving overload
  • Juggling
  • Mothering alone
  • Real-life worry
• Repeating ideas


  • "I wasn't prepared for this baby," "I didn't want to have any more children"
  • "Please stop crying," "I need a break," "I can't do this anymore"
  • "No time to breathe," "Everyone depends on me," "Navigating the maze"
  • "I really don't have any help," "My baby has no father"
  • "I don't have any money," "Will my baby be OK?" "It's not safe here"
• Case Study Design


  • In-depth study and detailed description of a single individual (or a very small group)
  • May involve an intervention or treatment administered by the researcher
  • Case history: a case study without any treatment or intervention
• Applications of the Case Study Design

  • Rare phenomena and unusual clinical cases
  • Gaining information about mental disorders such as multiple personality disorder
  • Studying individuals with brain injuries and their underlying neurological mechanisms
  • Demonstrating an exception to the rule via a detailed description of a single individual
• Survey Research

  • Quantitative, qualitative and non-experimental and has two common characteristics:
  • The variables of interest are measured using self-reports (Respondents report on their own thoughts, feeling or behaviours)
  • Uses large random samples
• Where did Survey Research come from

  • Survey research has its roots in applied social research, market research, and election polling
  • It has since become an important approach in many academic disciplines, including political science, sociology, public health, and, of course, psychology
• The Survey Research Design

  • A research study that uses a survey
  • Obtains a description of a particular group of individuals
  • Goal: obtain a "snapshot" of the group at a particular time
  • Common application: companies seeking accurate descriptions of their customers
  • Results describe the variables being studied