13.00 o9 t scott

13.00 o9 t scott

• 1.
  The Concept ofForce and the Mechanics Curriculum Terry Scott Statistician Not a Statistician Andrew Gray Daniel Schumayer Minion
• 2.
  The Force ConceptInventory • Concept Inventory rather than a “test”. • 30 multichoice questions. • Very good distractors: – Guessing success very low – Reliability unusually high – Pre and post test design seems to work well
• 3.
  The Force ConceptInventory
• 4.
  FCI - Uses •Standard uses: – Evaluate development of conceptual understanding. – Evaluate teaching methods. • Our research: – Search for conceptual coherence. – Understand associations in student mind. – Inform teaching method. – Suggest future research.
• 5.
  Data Collection • FCIdelivered online (Blackboard) • PHSI191 – Large Health Science service course. • 2000 student responses collected over two years, 2008 and 2009. • Not obligatory. • Data checked for disengaged responses – 50 response sets removed.
• 6.
  Data Analysis • ExploratoryFactor Analysis – Construct correlation matrix (using tetrachoric correlations) – Find eigenvalues/eigenvectors. • What does this mean? – Factors = latent traits/concepts – Factors represent student understanding of force. • How do students group questions, which questions are about the same thing? • How does this compare with the way experts group questions?
• 7.
  Interpretation • 5 factorsfound in the analysis. • These factors are not orthogonal – Correlations between factors – useful information • Clear that there is conceptual coherence in the data. • Better score = greater conceptual coherence? – No evidence, not enough data
• 8.
  The Factors • Factor1 – Identification of forces. • Factor 2 – Newton’s first law, linear and curved paths. • Factor 3 – Newton’s second law + necessary concepts (acceleration, velocity). • Factor 4 – Newton’s first law with zero net force. • Factor 5 – Newton’s third law.
• 9.
  Factor 1 –Identification of Forces.
• 10.
  Factor 2 –Newton’s First
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  Factor 3 –Newton’s Second
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  Factor 4 –Newton’s First Again
• 13.
  Third Law/First Lawconflation – Qu.16
• 14.
  Kinematics? • Authors ofthe FCI included a number of questions solely about kinematics concepts. • We find no factor containing only kinematics questions. • Kinematics questions are distributed “where they are needed” in factors about force laws.
• 15.
  Item Response Analysis- Preliminary • Preliminary results • Show third law questions significantly higher difficulty that other questions • Marginal analysis – Assess student ability, predict the questions they will get right. – Anomalous numbers of students get 3rd law questions right but 1st and 2nd law questions wrong.