To avoid the problem associated with conflicting results produced by the
conventional unit root tests*such as Dickey and Fuller (1979, 1981), Kwaitkowski
et al. (1992) and Phillips and Perron (1988) tests*when these tests are used jointly,
we use the bounds testing approach for co-integration in this study. Firstly, I consider
only the bivariate long-run relationship between OFDI and GDPP. Then, two
additional variables, DI and OPEN are added as control variables. These two control
variables are introduced in the multivariate long-run relationship in order to capture
the country specific effect