Manhattan Beach-based shoe company Skechers was this week’s biggest mover, gaining 18 percent to end at $27.78. Activision Blizzard was also among the week’s biggest movers. The Santa Monica-based gaming and entertainment company gained 18 percent to end at $47.23. Wesco Aircraft Holdings Inc. of Valencia was the week’s biggest loser, dropping 15 percent to end at $12.95.