Calculate confidence score of document
How about adding up/taking the mean of your title scores(since they'd be on the same scale) and content scores for all the methods so now you'll have a single title score and single content score. 
To get a single score for a document, you'll have to combine the title and content scores. To do that, you can take a weighted average(you'll have to decide the weights) or you can multiply these scores to get a single metric. Although these may not be close to zero or one, as is your requirement
As an alternate method, you can create a dataset with the added/averaged up title scores and content scores and manually create the confidence score column with zeros and ones. Using this data you can build a logistic regression model to classify your documents with confidence scores of zeros and ones. This will give you the weights as well and more insight to what you are actually looking for
Using different methods, I am scoring documents & it's title. Now I want to aggregate all these scores into single score(confidence score). I want to use unsupervised method. I want confidence score in terms of probability or percentage.
Here , M= Method No, TS = document title score, CS = document content score
eg 1
Doc1 (expected confidence score close to 0)
M - TS - CS
1 - 0.03 - 0.004
2 - 0.054 - 0.06
3 - 0.09 - 0.12
Doc2 (expected confidence score close to 1)
M - TS - CS
1 - 0.50 - 0.63
2 - 0.74 - 0.90
3 - 0.615 - 0.833
Here my hypothis is confidence score should be colse to zero for document-1 and close to 1 for document-2.
It is also possible that all Documents will have lower scores for all the methods(eg 2), so the confidence scores should be close to zero for all documents.
eg.2
Doc1 (expected confidence score close to 0)
M - TS - CS
1 - 0.03 - 0.004
2 - 0.054 - 0.06
3 - 0.09 - 0.12
Doc2  (expected confidence score close to 0)
M - TS - DS
1 - 0.001 - 0.003
2 - 0.004 - 0.005
3 - 0.0021 - 0.013 
Can anyone explain me or provide some resource to calculate confidence score?