Applying Meta-Frontier Approaches to Profitability Estimation: In Case of the Effects of Official Independent Directors

Table 1

Variable definitions.

Variable attribute	Variate	Definition
Output variable	Y	Annual operating income of listed textile enterprises (RMB million)
Input variable	L	Total input labor force (thousand people)
	K	Total investment in fixed assets, intangible assets and other long-term assets (RMB million)
Director	GOV	Official independent director employed by listed company in current year = 1
Environment variables	HHI	Market concentration
	AGE	Business year (year)
	CITY	Company located in a municipality = 1
	COASTAL	Company located in a coastal province = 1