倒排索引和term-document关联矩阵

Web信息处理第三次作业

PB10210016徐波

考虑下面的文档：
    Doc 1    new home sales top forecasts 
    Doc 2    home sales rise in july 
    Doc 3    increase in home sales in july 
    Doc 4    july new home sales rise
（1）画出该文档集对应的term-document关联矩阵，假定每个单词都作为一个索引词项
（2）画出该文档集对应的倒排索引，假定每个单词都作为一个索引词项。要求每个词项包含document frenquency以及term frenquency

（1）

	doc1	doc2	doc3	doc4
new	1	0	0	1
home	1	1	1	1
sales	1	1	1	1
top	1	0	0	0
forecasts	1	0	0	0
rise	0	1	0	1
in	0	1	1	0
july	0	1	1	1
increase	0	0	1	0

(2)

	doc.freq	trem.freq
new	2	1 [freq.=1]; 4 [freq.=1]
home	4	1 [freq.=1]; 2 [freq.=1]; 3 [freq.=1]; 4 [freq.=1];
sales	4	1 [freq.=1]; 2 [freq.=1]; 3 [freq.=1]; 4 [freq.=1];
top	1	1 [freq.=1];
forecasts	1	1 [freq.=1];
rise	2	2 [freq.=1]; 4 [freq.=1];
in	3	2 [freq.=1]; 3 [freq.=2];
july	3	2 [freq.=1]; 3 [freq.=1]; 4 [freq.=1];
increase	1	3 [freq.=1];