Sufficient condition for stabilization of linear time invariant fractional order switched systems and variable structure control stabilizers

► Men's additional income from their guest-worker employment generates a pure income effect, which increases fertility. ► The timing of women's higher-wage employment relative to child bearing is crucial for its effect on fertility. ► If women work abroad during the same time period when they can bear children, their additional income reduces fertility. ► Otherwise, the effect is not different from that of men's additional income.