I plan to filter an input document using 4 different labels.
Just for an example, a document discussing about movie summary needs to be labeled with 4 labels (Romance, Drama, Fiction, Hollywood). Only if it is labeled with these specific 4 labels, will it be considered as a "PASS". A lack of either of the labels should mark the document as "Fail"
PASS = ["romance", "drama", "fiction", "hollywood"]
FAIL = ["romance", "drama", "fiction", "chinawood"]
In terms of labels "pass" or "fail", it is a binary classification problem, but in terms of these 4 labels, it is a multi-label document classification problem.
Additionally, I do not have a lot of documents that are tagged with these 4 labels simultaneously. So, I thought of decomposing the problem into a binary classification problem after reading this and using ensemble methods to chain individual binary classifiers together.
However, I have a built a set of 10,000 documents for each class ("Romance" vs "Not romance"), ("Drama" or "Not drama"), ("Fiction" or "Not fiction") and ("Hollywood" or "Not hollywood").
Classifier 1: ("Romance" or "Not romance")
Results of classifier 1 are input to the classifier 2
Classifier 2 ("Drama" or "Not drama")
Results of classifier 2 are input to the classifier 3
Classifier 3 ("Fiction" or "Not fiction")
Results of classifier 3 are input to the classifier 4
Classifier 4 ("Hollywood" or "Not hollywood")
Results of classifier 4 are the final set of set of documents labeled with the four labels.
In thisway, it becomes a hierarchical Multi-label problem.
Note: The movie genre labels are just used for the example. The real problem here connects with very precise medical/health labels (For example ["Lung Cancer", "Adult Female", "Journal Report", "Asian"]). Hence, the training document set that has all the four labels simultaneously is very small. This forced me to think towards decomposing the problem into a binary classification problem.
Additional Note: This is my first machine learning project and I am quite new to this task.
So my question was, if I was heading the right direction or should I read more into it? Any hint or constructive criticism is welcome.