These hypotheses generally deal with relationships between concepts or variables. Loosely A causes B. Or, knowing information about A will tell you something about B. Most empirical work in academic journals like the Academy of Management use formal hypotheses. Formal hypotheses are used in experimental and quasi experimental design. They are used in formal evaluation research. A formal hypothesis can be either conceptual or operational.
Conceptual hypotheses are at the abstract level.
They are not tied to a study design. Null Hypothesis A type of formal hypothesis that states that two variables are not related in the population. It is the null hypothesis that is actually tested by tests of statistical significance. Generally a null hypothesis is paired with a formal research hypothesis. In program evaluation the guiding formal hypothesis would be that the program influences the outcome.