Measuring practices are the assumptions, constraints, theories, approaches and scales an organization adopts and uses in order to support valid and reliable findings. Validity is concerned with accuracy, correctness, truthfulness, whereas; reliability is concerned with consistency, reproducibility, redundancy.

Therefore, measurement practices must support both valid and reliable concepts. The chart below shows the different types of validity and reliability.What factors determine if a measurement practice is both valid and reliable?
  • Authorities: who in terms of person or organization indicates it is so
  • Experience: what empirical evidence supports the hypothesis
  • Proof: where in history can we find situations that indicate this is a recommended approach
  • Timeframe: when is it considered applicable, knowing that things change over time
  • Rationale: why is it considered to be so
  • Justification: how were the conclusions arrived at
  • Standards: which guidelines or rules substantiate it
What are some good examples of measurement practices that are both valid and reliable?
  • Project Management Body of Knowledge (PMBOK) published by PMI (version updates based upon industry input)
  • OMBOK published by APICS
  • ISO Standards: ISO has developed over 18,500 International Standards
  • IEEE Standards
  • OSHA Regulations
  • FDA Compliance Guidelines
  • ANSI Standards
Note: For this reason, this website purposes to represent LL in the context of valid and reliable measurement practices by setting its foundation on references such as the PMBOK, PRINCE2, OMBOK and Evaluation Thesaurs (Scriven).

Forms of Validity

  • Construct Validity
  • Criteria (criterion)-related Validity
  • Concurrent validity
  • Content Validity
  • Consequential Validity
  • Convergent Validity
  • Discriminant Validity
  • Face Validity
  • Predictive Validity

Forms of Reliability

  • Inter-Rater or Inter-Observer Reliability
  • Test-Retest Reliability
  • Parallel-Forms Reliability
  • Internal Consistency Reliability

Measurement can help organizations determine effectiveness and efficiency:

  • Effectiveness: "best use" of resources to achieve outcome, i.e., performance in how well, how strong, or how good.
  • Efficiency: " least cost" of a preferred solution, i.e., saving, minimizing, or streamlining.

Measurement practices include a host of activities that focus on a variety of end points. For example:

  • Benchmarking: Comparative analysis and competitive analysis
  • Estimating: Budgeting (i.e., EVM - Earned Value Management) and Calculating (i.e., ROI - Return on Investment)
  • Predicting: Forecasting and TrendingWhile measurement relies heavily on the use of descriptive statistics or number crunching, it is more than just determining:
  • Mean: summed scores divided by number of scores
  • Mode: most frequently occurring score
  • Median: 50% of cases in distribution fall below/above
  • Ratio: a way of comparing two quantities by dividing them, i.e., 2 to 3
  • Percentage: a proportion in relation to a whole, i.e., 25%
  • Sample Size: number of observations that constitute it