What makes stock prices move?

It is information, I would say - and expectations.

Even though the strong-form market efficiency theory primarily shaped by Fama, French and Jensen might not hold entirely, I am convinced that stock prices are only responsive to different pieces of news thrown at the market - leading to the assumption that econometric analysis of price movements is not an accurate way of explaining them (even though some advanced econometric tools like the Engle-Granger GARCH processes allow to describe price movement patterns better than white noise processes, those patterns in my opinion only reflect responses to pieces of news). Furthermore, I believe that technical analysis is no serious approach to the problem, though the wide use of the concept might have led to the presence of "self-fulfilling prophecies" with respect to technical analysis.

Assuming that information and expectations are the only factors that makes stock prices move, the next question to be answered should be: Which piece of information (positive or negative, economic information or stock-specific) results in which movements depending on the state of the market (bull or bear) and the expectation level of the respective stock?

Maybe all those factors could lead to an information model of the stock market (or single stocks) helping companies to predict movements in their stock price, depending on the expectation level of the market with respect to the companies stock. Even though a large number of event studies have dealt with this problem - especially with the analysis of price movements in M&A processes, I think that so far there has been no paper trying to integrate all the factors into a single model.