Concise Data Processing Assessment (CDPA)

Developed by James Day and Doug Bonn

Purpose To probe student abilities related to the nature of measurement and uncertainty and to handling data.
Format Pre/post, Multiple-choice
Duration 30 min
Focus Lab skills (uncertainty in measurement, relationship between functions graphs and numbers)
Level Graduate, Upper-level, Intermediate, Intro college
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Sample question from the CDPA:

Student A measures the flow rate of water coming from a tap and reports it to be (90 ± 12) millilitres per second. Student B follows a different measurement procedure and reports the flow rate to be (110 ± 1) millilitres per second. How long would it take to fill a 1 litre container?

(a) 10.0 s
(b) 9.1 s
(c) 11.1 s
(d) 9.5 s
(e) 10.6 s

CDPA Implementation and Troubleshooting Guide

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J. Day and D. Bonn, Development of the Concise Data Processing Assessment, Phys. Rev. ST Phys. Educ. Res. 7 (1), 010114 (2011).
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Gold Star Validation
This is the highest level of research validation, corresponding to all seven of the validation categories below.

Research Validation Summary

Based on Research Into:

  • Student thinking

Studied Using:

  • Student interviews
  • Expert review
  • Appropriate statistical analysis

Research Conducted:

  • At multiple institutions
  • By multiple research groups
  • Peer-reviewed publication

The multiple-choice questions on the CDPA were developed based on established learning goals for an introductory lab course. Open-ended questions were created based on these learning goals, and given to students, of whom a subset were interviewed about their answers. Next, multiple-choice versions of the questions were created and given to students and followed-up with more student interviews. The CDPA also underwent expert review. Appropriate statistical analysis of reliability, difficulty and discrimination was conducted and reasonable values found. The CDPA has been given to over 800 students at two institutions and the results published in one peer-reviewed paper. 


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Typical Results

Typical results from Day and Bonn 2011:

Incoming first-year students at the University of British Columbia (UBC) and at the University of Edinburgh perform about at the level of chance on the CDPA. Random guessing produces a score of 23.5%. Fourth-year students at UBC (N = 75), without ever having taken a course that addresses these data handling skills explicitly, score around 47 ± 3%. Graduate students (N = 32) score at 53± 4% and faculty score at 80 ± 4%.

The latest version of the CDPA, released in 2014, is version 2. Version 1 was published in 2011 (Day and Bonn) and has all ten questions. There were very minor changes between the two versions.