Hypothesis Format

• If you have a strong theory, you can cleanly predict what happens to Y if you change X.
• In that case, it makes most sense having formal hypotheses in your paper.
• For example, see Datta, Foubert and van Heerde (2015, JMR, https://doi.org/10.1509/jmr.12.0160 )

Expectations

• If your theory is not strong, or your predictions are frequently going in both ways (e.g., both positive and negative), it’s wiser to not write out formal hypotheses but rather expectations.
• For a paper having expectations, see Datta, Ailawadi , and Van Heerde (2017, paper here). Alternatively, a paper can very well do without any hypotheses or expectations, see here.

Important: choose a format that fits your research!