Province^b

Independent

Dependent

Length of railways in operation (km)

Length of highways (km)

Correlation between independent variables

Shaanxi

TVEI

(100 thousand USD)

0.823**

0.928**

0.893**

Gansu

TVEI

(100 thousand USD)

−0.330

0.205

0.837**

Qinghai

TVEI

(100 thousand USD)

0.517

0.469

0.943**

Ningxia

TVEI

(100 thousand USD)

0.675*

0.833**

0.691*

Xinjiang

TVEI

(100 thousand USD)

0.203

0.285

0.966**