Radial Big Data Models
When the number of decision-making units is large, traditional DEA models are slow to solve. Khezrimotlagh, Zhu, Cook, and Toloo (2019), propose a framework that reduces the computational time by finding the set of best practices DMUs from a subsample and evaluating the rest of the decision-making units with respect to the best performers.
The proposed framework includes five steps:
- Select a subsample of DMU.
- Find the best practices in the subsample.
- Find the exterior DMUs with respect to the hull of the best practices.
- Identify the set of all efficient DMUs.
- Calculate performance scores as in the traditional DEA model.
This example computes the Big Data radial input-oriented DEA model under variable returns to scale, using random data drawn from a uniform distribution. 500 DMUs with six inputs and four outputs in the interval (10, 20) are generated:
# Generate random data
using DataEnvelopmentAnalysis
using Distributions
using Random
using StableRNGs
rng = StableRNG(1234567)
X = rand(Uniform(10, 20), 500, 6);
Y = rand(Uniform(10, 20), 500, 4);
# Calculate the Big Data DEA Model
deabig = deabigdata(X, Y)
# Get efficiency scores
efficiency(deabig)500-element Vector{Float64}:
1.0
0.9952033543185781
1.0
0.7910328000985023
0.9102118874690652
1.0000000000000004
0.8442435774414491
0.7529134702454395
0.947081903569938
0.9999999999999998
⋮
0.9015758511495415
1.0
0.9256780314048102
0.9999999999999998
0.803633045007155
1.0000000000000002
1.0
0.8261580618825146
0.7969301173257913deabigdata Function Documentation
DataEnvelopmentAnalysis.deabigdata — Function
deabigdata(X, Y)Compute the big data radial model using data envelopment analysis for inputs X and outputs Y.
Optional Arguments
orient=:Input: chooses the radially oriented input mode. For the radially oriented output model choose:Output.rts=:CRS: chooses constant returns to scale. For variable returns to scale choose:VRS.atol=1e-6: tolerance for DMU to be considered efficient.names: a vector of strings with the names of the decision making units.