In summary, it would be unwise to place too much weight on the precise figure of -
0.0185. The hint of endogeneity and the large coefficient in the provinces model both
suggest that the true effect may be larger, at least for private employees. However, it is
still useful to compare this figure with estimates obtained from developed countries. Most
such estimates have come from regressing log wages on migrant share. Our estimate can
be made approximately comparable to these by dividing by the mean migrant share
(Longhi et al 2005). The mean share of Myanmar migrants is 0.016, so our estimate
translates to about -1.2 from previous studies. This is a considerably larger in absolute
value than Longhi et al’s (2005) median value of -0.119, though smaller than the values
of -3 to -4 found by Borjas (2003).
Even so, the impact of immigration on overall labor market outcomes in Thailand should
not be overstated. A coefficient on migrant intensity of -0.0185 implies that immigration
sufficient to double migrant numbers in 10 years would reduce wage growth by one tenth
of a percentage point per year.