In the first chapter titled "Cognitive Ability, Education, and Fertility Risk", I explore the role of cognitive ability in fertility timing. Women in the bottom quartile of the cognitive ability distribution are nine times more likely to have their first child as a teenager. First, I document the differences in age at childbirth by…

The objective of this research is to comparatively analyze the performance of two generations of children (as first generation of immigrants) attending primary and secondary education in different geographical areas, evaluated in different decades but with equivalent age brackets. Two samples of 169 immigrant school populations in Portugal, with…

Patterns of maintenance of ability across the life span have been documented on tests of knowledge ("Gc"), as have patterns of steady decline on measures of reasoning ("Gf/Gv"), working memory ("Gsm"), and speed ("Gs"). Whether these patterns occur at the same rate for adults from different educational…

Many Flynn effect (FE) studies compare scores across different editions of Wechsler's IQ tests. When construct changes are introduced by the test developers in the new edition, however, the presumed generational effects are difficult to untangle from changes due to test content. To remove this confound, we use the same edition of Wechsler…