Group type

Variable

Test type (c, t) test

ADF test

Stability (α = 5%)

Conclusion

Test method

P value

Developed country

Ln(GNI)

(c, t)

LLC

0.0178**

¹Instable

Ln(GNI) ~ I(1)

Breitung

0.1130

IPS

0.1020

ADF

0.1253

PP

0.1108

D(Ln(GNI))

(c, 0)

LLC

0.0000

Stable

Breitung

-

IPS

0.0000

ADF

0.0001

PP

0.0000

Ln(FDI)

(c, t)

LLC

0.4053

Instable

Ln(FDI) ~ I(1)

Breitung

0.6198

IPS

0.2194

ADF

0.2123

PP

0.3880

D(Ln(FDI))

(c, 0)

LLC

0.0006

Stable

Breitung

-

IPS

0.0001

ADF

0.0005

PP

0.0001

(Ln(FDI))²

(c, t)

LLC

0.1663

Instable

(Ln(FDI))² ~ I(1)

Breitung

0.4188

IPS

0.0522***

ADF

0.0572***

PP

0.2689

D[(Ln(FDI))²]

(c, 0)

LLC

0.0036

Stable

Breitung

-

IPS

0.0001

ADF

0.0007

PP

0.0001