Comparing DEA Analysis Professional (ex-KonSi) to Other DEA Tools

How to Use DEA Analysis Professional (formerly KonSi DEA) for Efficiency MeasurementData Envelopment Analysis (DEA) is a non-parametric method used to evaluate the relative efficiency of decision-making units (DMUs) — such as firms, hospitals, schools, branches, or production lines — that consume multiple inputs to produce multiple outputs. DEA Analysis Professional (formerly KonSi Data Envelopment Analysis DEA) is a dedicated software tool that implements DEA models, offers data management, allows model selection and customization, and produces detailed reports and visualizations for efficiency analysis.

This article explains — step by step — how to use DEA Analysis Professional to measure efficiency, choose appropriate DEA models, prepare and import data, run analyses, interpret outputs, and apply results to practical decision-making. It also covers common pitfalls, advanced features, and best practices.


Overview: What DEA Analysis Professional Does

DEA Analysis Professional provides:

  • Model selection: CCR, BCC, input- or output-oriented models, super-efficiency, and others.
  • Data management and validation tools.
  • Efficient frontier computation and projection of inefficient DMUs.
  • Slack and sensitivity analysis.
  • Statistical outputs and graphical visualizations (efficiency scores, peer groups, target recommendations).
  • Exportable reports for presentations and decision support.

When to use DEA

Use DEA when:

  • You need to compare units that use multiple heterogeneous inputs and produce multiple outputs.
  • There is no reliable price information to build a parametric production function.
  • You want relative efficiency measures (frontier-based) rather than average or regression-based metrics.
  • Sample size is reasonable: a common rule of thumb is at least 3×(number of inputs + outputs) DMUs for stable results.

Key limitation: DEA is deterministic and sensitive to outliers and measurement error; complement DEA with sensitivity analysis or bootstrap methods where possible.


Preparing your analysis

1) Define the decision-making units (DMUs)

  • Identify comparable units (same objectives, similar operating environment).
  • Ensure units are homogeneous in function; do not mix dissimilar operations.

2) Select inputs and outputs

  • Inputs: resources consumed (labor hours, cost, machines, beds, etc.).
  • Outputs: desirable results (sales, patients treated, graduates, units produced).
  • Avoid mixing inputs and outputs incorrectly; each variable should be clearly input or output.
  • Keep the number of variables moderate relative to DMU count to avoid rank deficiency and too many units scoring 1 (efficient).

3) Data collection and cleaning

  • Use the same measurement units across DMUs.
  • Check for missing values, outliers, or zero values where infeasible.
  • Normalize or scale data if appropriate (DEA is scale-invariant for ratio data in many models but inconsistent scaling can affect numerical stability).

Getting started in DEA Analysis Professional

Installation and setup

  • Install the software following the vendor’s instructions.
  • Create a new project and set a descriptive project name and metadata (date, analyst, domain).
  • Configure workspace options such as default model types, precision, and output folders.

Importing data

  • DEA Analysis Professional typically supports CSV, Excel, and direct database connections.
  • Prepare a tabular file: first column DMU identifiers; subsequent columns inputs and outputs. Include a header row with variable names.
  • Use the import wizard to map columns to inputs/outputs and to set variable types (input/output, ordinal/continuous).

Example data layout:

DMU, LaborHours, CapitalCost, Outputs_Sales, UnitsProduced BranchA, 1200, 25000, 500000, 1200 BranchB, 900, 18000, 420000, 950 ... 

Data validation inside the tool

  • Run the built-in validation to locate missing values, negative or zero inputs/outputs (if inappropriate), and dominate variables.
  • Use descriptive statistics and histograms provided by the tool to visualize distributions and spot outliers.

Choosing a DEA model

DEA Analysis Professional offers several common models:

  • CCR (Charnes–Cooper–Rhodes): Assumes constant returns to scale (CRS). Use when DMUs operate at an optimal scale.
  • BCC (Banker–Charnes–Cooper): Assumes variable returns to scale (VRS). Use when scale inefficiencies are likely.
  • Input-oriented vs Output-oriented: Choose input-oriented when the goal is to minimize inputs for a given output; choose output-oriented when maximizing outputs with given inputs is the goal.
  • Additive, SBM (slack-based measure), and non-radial models: Use for direct treatment of slacks and when radial measures obscure inefficiencies.
  • Super-efficiency models: Rank efficient DMUs beyond the standard efficiency score of 1.

Choose model based on:

  • Economic/operational question (minimize inputs vs maximize outputs).
  • Scale assumptions (CRS vs VRS).
  • Need to rank efficient DMUs.

Running the analysis

  1. Select DMUs and variables.
  2. Choose model type and orientation.
  3. Set solution options:
    • Precision and numerical tolerance.
    • Return-to-scale restrictions (CRS/VRS).
    • Constraints (weight restrictions, assurance regions) if you want to reflect prior knowledge or limit unrealistic weightings.
  4. Run the calculation.

DEA Analysis Professional computes:

  • Efficiency scores (θ for input-orientation; φ for output-orientation).
  • Reference sets/peer groups for each DMU.
  • Target input/output levels and slack values.
  • Dual variables (weights) and lambda values (intensity vectors).

Interpreting results

Core outputs

  • Efficiency score: Values ≤ 1 for input-oriented models (1 = efficient; = inefficient). For output-oriented scores, values ≥ 1 indicate efficiency (1 = efficient).
  • Peers/reference set: Efficient DMUs that form the convex combination that projects the inefficient DMU onto the frontier.
  • Targets: Suggested proportional reductions in inputs (input-oriented) or expansions in outputs (output-oriented) to reach the frontier.
  • Slacks: Non-proportional adjustments needed after radial projection.

Example interpretation

  • Branch X has input-oriented efficiency 0.78: it should reduce inputs by 22% (in radial terms) to reach the frontier; additional slacks indicate further specific input cuts.
  • Branch Y is efficient (score 1) and appears in several peers lists, indicating best-practice status.

Advanced diagnostics & robustness

Sensitivity and influence analysis

  • Jackknife or leave-one-out analysis: Check how removal of single DMUs affects others’ efficiency.
  • Bootstrapping (if supported): Obtain confidence intervals for efficiency scores to assess statistical significance.

Weight restrictions and assurance regions

  • If DEA assigns unrealistic zero weights to important outputs, impose restrictions to reflect managerial priorities or economic logic.

Super-efficiency and ranking

  • Use super-efficiency models to rank efficient DMUs and to perform outlier detection; be cautious as super-efficiency can be unstable if data contain outliers.

Visualizing and exporting results

  • Use graphics (efficiency histograms, frontier plots, target arrows) to communicate findings.
  • Export tables and charts to Excel, CSV, or PDF for reporting.
  • DEA Analysis Professional often provides peer network diagrams and efficiency decomposition charts — use these for stakeholder presentations.

Common pitfalls and how to avoid them

  • Too many variables relative to DMUs: reduces discriminatory power — follow the rule-of-thumb minimum DMU count.
  • Mixing heterogeneous units: compare only comparable DMUs.
  • Ignoring outliers: extreme DMUs can distort the frontier. Identify and decide whether to exclude, Winsorize, or analyze separately.
  • Overreliance on DEA alone: combine results with qualitative assessment and other quantitative methods (stochastic frontier analysis, regression) when possible.

Practical example (brief)

  1. Problem: Evaluate 30 bank branches using 3 inputs (staff hours, operating cost, branch area) and 2 outputs (new accounts, loan volume).
  2. Model: BCC input-oriented because branches vary in scale and the goal is to reduce resource use.
  3. Run DEA Analysis Professional: import data, validate, choose BCC input-oriented, run analysis.
  4. Results: 8 branches efficient (score 1); inefficient branches have radial reductions between 10–45%. Peers identified for each inefficient branch with target input mixes and slack adjustments.
  5. Action: Managers use targets to set resource reduction plans and investigate operational differences with peer branches.

Best practices checklist

  • Ensure DMU homogeneity.
  • Keep input/output count reasonable given sample size.
  • Clean and validate data thoroughly.
  • Choose model orientation that matches managerial objectives.
  • Use weight restrictions when economic logic requires.
  • Run sensitivity/robustness checks (leave-one-out, bootstrap).
  • Visualize results and translate targets into actionable steps.

Final notes

DEA Analysis Professional (formerly KonSi DEA) is a powerful tool when used with care: define the problem clearly, prepare data appropriately, select the right model, and interpret results in context. Combine DEA outputs with managerial insights and robustness checks to drive meaningful efficiency improvements.

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