Table 2 Dimensions and variables for the DE Index.

From: How does the digital economy enhance carbon emission efficiency in the logistics industry? Empirical evidence from 30 Chinese provinces

Variables

Details (unit)

Attribute

Infrastructure

Fiber optic cable line length (10,000 km)

+

Mobile phone exchange capacity (10,000 households)

+

Internet broadband access ports (10,000)

+

Industrial scale

Total telecommunication services (100 million yuan)

+

Revenue from main business of telecommunication industry (100 million yuan)

+

Revenue from software operations (100 million yuan)

+

Employed people engaged in information transmission, software and information technology services in urban units (10,000 persons)

+

User scale

Internet broadband access subscribers (10,000 households)

+

Digital television user (10,000 households)

+

Number of web pages (10,000)

+

Number of domains (10,000)

+

Mobile phone penetration (department/hundred people)

+

Mobile subscribers at year-end (10,000)

+