frontier

frontierCost

Description

The frontierCost action analyzes stochastic frontier cost models. It estimates the cost efficiency of decision-making units by formulating a cost function that accounts for both random error and non-negative inefficiency components. This action is essential for benchmarking performance and identifying deviations from the optimal cost frontier given input prices and output levels.

Settings
ParameterDescription
tableSpecifies the input data table to be analyzed. This is a required parameter.
modelSpecifies the dependent variable, explanatory effects (regressors), and specific model options (like efficiency type). This is a required parameter.
classSpecifies the classification variables to be used in the analysis.
boundsImposes simple boundary constraints on the parameter estimates.
optimizerControls the nonlinear optimization process, including the algorithm (e.g., Newton-Raphson, Conjugate Gradient) and convergence criteria.
outputSpecifies details for the output data table, which can contain predicted values, residuals, and technical efficiency estimates (te1, te2).
restrictionsSpecifies linear restrictions to be imposed on the parameter estimates.
testsSpecifies linear hypotheses about the regression parameters to be tested (Wald, Lagrange Multiplier, Likelihood Ratio).
weightSpecifies the variable to be used as the observation weight.
freqSpecifies the variable to be used as the observation frequency.
Data Preparation View data prep sheet
Creation of Simulated Cost Data

Generates a dataset simulating cost, output, and input prices for 100 firms, including a random inefficiency term.

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1 
2DATA casuser.cost_data;
3call streaminit(12345);
4DO i = 1 to 100;
5log_output = rand('Normal', 1, 0.5);
6log_price1 = rand('Normal', 0.5, 0.2);
7log_price2 = rand('Normal', 0.5, 0.2);
8v = rand('Normal', 0, 0.1);
9u = abs(rand('Normal', 0, 0.2));
10log_cost = 0.5 + 0.8*log_output + 0.4*log_price1 + 0.6*log_price2 + v + u;
11OUTPUT;
12END;
13 
14RUN;
15 
16PROC CASUTIL;
17load
18DATA=casuser.cost_data casout="cost_data" replace;
19 
20RUN;
21 

Examples

Estimates a simple Cobb-Douglas stochastic frontier cost model using the default exponential distribution for efficiency.

SAS® / CAS Code Code awaiting community validation
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1 
2PROC CAS;
3frontier.frontierCost TABLE="cost_data", model={depVars={{name="log_cost"}}, effects={{vars={"log_output", "log_price1", "log_price2"}}}};
4 
5RUN;
6 
Result :
Generates parameter estimates for the cost function and the inefficiency variance components.

Estimates a model specifying a Half-Normal efficiency distribution, custom optimization settings, and generates an output table containing technical efficiency scores.

SAS® / CAS Code Code awaiting community validation
Copied!
1 
2PROC CAS;
3frontier.frontierCost TABLE="cost_data", model={depVars={{name="log_cost"}}, effects={{vars={"log_output", "log_price1", "log_price2"}}}, modelOptions={type="HALF"}}, optimizer={algorithm="QUASINEWTON", maxit=200}, OUTPUT={casOut={name="frontier_scores", replace=true}, te1="TechEff", pred="PredictedCost"};
4 
5RUN;
6 
Result :
Produces model estimates using the Half-Normal type and creates a CAS table 'frontier_scores' containing technical efficiency (TechEff) and predicted cost values.

FAQ

What is the primary purpose of the frontierCost action?
How do I specify the input data for the analysis?
How can I define the stochastic frontier model to be estimated?
What types of frontier models are supported by the frontierCost action?
How can I obtain estimates for technical efficiency in the output table?
Is it possible to perform hypothesis tests on the regression parameters?
How are classification variables handled in the model?
What optimization algorithms are available for parameter estimation?
How can I save specific display tables, such as parameter estimates, as CAS tables?
Can I provide custom initial values for the model parameters?