Untitled Flashcards Set

Single Factor Design

Single Factor Design Decision Tree

Single-Factor Two Levels

• Between subjects, single factor designs

  • Independent groups designs

    • Manipulated independent variable

    • Random assignment to create equivalent groups

    • Example

      • IV: manipulated type of note-taking (laptop note taking vs handwritten note taking)

      • DV: performance on memory test

  • Matched groups design

    • Manipulated independent variable

    • Matching to produce equivalent groups

    • Example

      • IV: type of social skills training (Direct teaching vs play activities)

      • Matching variable: autism quotient

      • DV: social interaction observation code

  • Ex-Post Facto Designs

    • Subject variable as an independent variable

    • Deliberate attempts to select participants to reduce nonequivalence

    • Example

      • IV: whether or not traumatic brain injury has occurred

        • Experimental group: had experience TBI

        • Control group: no TBI

      • DV: ability to detect insincerity others

• Within-subjects, single factor designs

  • Also called repeated measures designs

    • Famous historical example: Stroop

    • used reverse counterbalancing

    • manipulated independent variable

    • all subjects participate in all levels of the independent variable

      • Each participant is their own control

    • IV: color of ink

      • Control group: NC

      • Experimental group: NCWd

    • DV: time to read

• Between-subjects, multilevel designs

  • Advantage 1: ability to discover nonlinear effects

  • Advantage 2: ability to rule out alternative explanations

    • Power posing gone wrong

      • Compared just high and low power

      • Could have added a control group and been better controlled

Analyzing Data from Single-Factor Designs

• Presenting the data

  • Don’t present the same data in more than one way

  • Each way has its own pros/cons and some data is best presented in a certain way

  • Bar graphs vs line graphs - bar graph better

  • Bransford and Johnson’s (1972) data presented in table and graphical forms

• Within-subjects, multilevel designs

  • Nonlinear results - line graph

    • Ebbinghaus forgetting curve

Analyzing Data: Inferential Statistics

• Key terms

  • Variability

    • Systematic Variance

    • Error Variance

    • Homogeneity of variance

Analyzing Data from Single-Factor Designs

• Analyzing single-factor, two-level designs

  • T-test assumptions

    • Interval or ratio scale data

    • Data normally distributed (or close)

    • Homogeneity of variance

  • T-test for independent samples for:

    • Independent groups designs

    • Nonequivalent groups design

  • T-test for related (dependent) samples for:

    • Matched groups design

    • Repeated measures designs

  • Multiple t-tests inappropriate

    • Increases chances of Type I error

  • One-factor Analysis of Variance (ANOVA) for:

    • Multilevel independent groups designs

    • Multilevel ex post facto designs

  • One-way ANOVA for repeated measures, for:

    • Multilevel matched groups designs

    • Multilevel repeated-measures designs

  • Once overall significant effect found, then post hoc testing

  • Comparing each level of IV against each other level