What are the macroeconomic forces that influence mortgage rates?

I have a pretty solid understanding of basic macroeconomics, but I’m unclear how the mortgage rates factor into the bigger picture. Most bonds tend to have an inverse relationship with the major stock indexes as I understand it (when the market is bullish, people want stocks, and when it’s bearish they want bonds). Demand for bonds usually drives up rates. Does this logic also apply to the mortgage market as well?

If I’m hoping lending rates fall back to where they were last week, what should I be tracking in the market? Is there a ticker? Do I want to see the DJIA go up? If you had to guess, what are the odds that rates will go up vs. going down over the next week or so?