Day 142 Hospital statistics regarding people who go to the emergency room after roller-skating accidents indicate the need for more protective equipment

Hospital statistics regarding people who go to the emergency room after roller-skating accidents indicate the need for more protective equipment. Within that group of people, 75 percent of those who had accidents in streets or parking lots had not been wearing any protective clothing (helmets, knee pads, etc.) or any light-reflecting material (clip-on lights, glow-in-the-dark wrist pads, etc.). Clearly, the statistics indicate that by investing in high-quality protective gear and reflective equipment, roller skaters will greatly reduce their risk of being severely injured in an accident.

Write a response in which you examine the stated and/or unstated assumptions of the argument. Be sure to explain how the argument depends on these assumptions and what the implications are for the argument if the assumptions prove unwarranted.

五问：

（1）“Within that group of people, 75 percent of those who had accidents in streets or parking lots had not been wearing any protective clothing (helmets, knee pads, etc.) or any light-reflecting material (clip-on lights, glow-in-the-dark wrist pads, etc.)”是事实，“Clearly, the statistics indicate that by investing in high-quality protective gear and reflective equipment, roller skaters will greatly reduce their risk of being severely injured in an accident”是结论，值得反驳吗？

（2）受伤了就一定要去 emergency room吗？换句话说，这个调查的取样是否可能存在问题？例如：有些人虽然穿了护具但是受伤了，又没去 emergency room，如果这样的情况很多，就会影响结论。

（3）文中提及了百分比（ 75 percent），在没有提供具体数量的情况下，百分比数字是否具有足够的说服力？而且，发生事故的主要原因一定是没有穿戴防护装备和反光设备吗？可能是轮滑者技术欠佳，做出一些危险动作或者比较粗心大意。另外，仅提及这 75%的人，却不讨论剩下的 25%，犯了我们常说的 impressed by large numbers的错误。

（4）重要的一点是，在意外事故中受伤的人未必是从事轮滑运动的人，如果伤者是行人，那么原文中强调的保护措施和反光材料是否有效？这种保护是否双向的？轮滑者速度过快有可能会撞到行人，轮滑者戴头盔、护膝并不会使行人免于受伤；而且行人也有可能会忽视轮滑者配备的反光设备。

（5）文中的调查强调了事故发生区域是街道与停车场，轮滑者是否可能在其他场所受伤？例如：小区、斜坡、河边。那文中所提及的防护措施还有效吗？文中是否给出了足够的信息来证明这一点？若是掉进河里，护具也不会起到很大的作用。