# How can I combine word2vec with tf-idf to have concatenated features?

I want to develop a focused crawler using deep reinforcement learning and a priority queue that will work as the crawler frontier. I reckon using x = (state, action) features as an input of a neural network, where the state is the current webpage fetched and the action are the out-links of the current page. That is, x = (state, action) will concatenate the state and the action features. The priority queue will use as a metric the Q-value of each out-link.

My main idea is to use a neural network that will use x = (state, action) as the input and produce for this action the equivalent Q-value. However, in order to create this feature space, I reckon using both word2vec and tf-idf.

For each state, I will use information about this page (text) and its parent pages (relevance frequency and other stats). For each action, I will use information about its anchor text and/or URL text.

1. I know that in word2vec each word has two-word representations. Which one should I use, the one that describes it as a center word?
2. Should I use TF-IDF or word2vec?
3. Can I combine them?
4. Can I use an LSTM-RNN with word2vec words as input to output document features?