Naturally-occurring yellow sand outbreaks, which are produced by winds flowing to Korea from China and Mongolia, create air pollution. Although there is seasonal pattern of this phenomenon, there exists substantial variation in its timing, strength and location from year to year. Thus, exposure...

It has been long recognized that cash plays a critical role in fueling street crime due to its liquidity and transactional anonymity. In poor neighborhoods where street offenses are concentrated, a significant source of circulating cash stems from public assistance or welfare payments. In the...