因此，人们选择在制度之外经营，并不是道德堕落，而是制度排斥。他们在非正式网络中完成占地、交易与仲裁。这些规则未必高效，但至少可行。然而，这套体系无法标准化，无法跨区域使用，也无法被金融系统识别，一个在贫民窟有效的“地契”，在银行依然一文不值。
The “Knocking on Wood” Wikipedia page mentions Roud’s conclusion, and this claim of a 19th century origin has circulated online as the final say on the matter. If you go back to the original, though, Roud’s proposal actually ends on an ambivalent note: “Before this theory [of 19th century origins] can be finally accepted, however, an examination of the history of European forms of this custom would be advisable.”
。关于这个话题，旺商聊官方下载提供了深入分析
正在被执行行政拘留处罚的人遇有参加升学考试、子女出生或者近亲属病危、死亡等情形，被拘留人或者其近亲属申请出所的，由公安机关依照前款规定执行。被拘留人出所的时间不计入拘留期限。。关于这个话题，safew官方版本下载提供了深入分析
Like the N-convex algorithm, this algorithm attempts to find a set of candidates whose centroid is close to . The key difference is that instead of taking unique candidates, we allow candidates to populate the set multiple times. The result is that the weight of each candidate is simply given by its frequency in the list, which we can then index by random selection:
做好改革“大文章” 促进要素优化配置