HESITANT DOMESTIC investors, tougher government regulations, and increased competition from other regional markets in 1994 helped arrest the previous year's growth spurt in Central Europe's pioneering Polish, Czech, and Hungarian stock markets. All three had been among the world's fastest-growing markets in 1993. A year later, in a paradoxical relationship between market performance and the performance of the economies as a whole, the national economies made strong recoveries while the markets contracted, especially in the latter half of the year.