na, M

form ine 6 nhan responsible for the national differences in economic gross domestic product (GDP) purchasing power parity economic freedom and an index of democracy and nations. These include differences in the designs of the IQ tests themselves, the numbers of people assessed in the various countries, the composition of the test-takers Intelligence 34 (2006) 4for 1998 per capita. They then regressed GDP in 1998growth and for the gap in per capita income between rich and poor nations ” (p. xv). To test their hypothesis empirically, Lynn and Vanhanen (2002) used mean IQ scores, first for 81 countries, and later using approxima-tions based on neighboring country scores yielding a total of 185 observations/countries. They have sinc