句子“as represented in The Bank of English” 里省略了什么?

句子“as represented in The Bank of English” 里省略了什么?
柯林斯双解词典引言里的一段 ：All the statements that COBUILD makes are based on an examination of the English language in use,as represented in The Bank of English.
译文：柯林斯词典所有的释义及用法说明均以对英语实际应用的分析研究为基础,在我们所使用的语料库The Bank of English中得到充分展示.
我的问题是“as represented in The Bank of English” represented 应该是被动,而这里被省略的主语是什么呢?语法上怎么理解比较好?