There appears to be some evidence to suggest that traditional (grade-school style) "graded homework" at the advanced undergrad and higher level may just not be particularly good pedagogy though [1]. If possible, it may be better to assign ungraded homework with complete guided solutions provided, plus regular in-class quizzes (the latter to motivate students to actually spend time on that assigned homework every week) [2].

[1] https://scholarlycommons.pacific.edu/soecs-facpres/16/ [2] https://www.tandfonline.com/doi/full/10.1080/00091383.2011.5...