The phrase "for assessment purposes" means that something is being done or collected for the purpose of evaluating, measuring, or determining something else. Full definition
In short, we seem to have students who believe that projects are for assessment purposes only. (edutopia.org)
In fact many of the counties where I obtained the sales information have even classified sales during these years as «not typical of market conditions» for tax assessment purposes. (nreionline.com)
Measurements are made in late July and early August on Columbia Glacier, recording the ablation during the first three months of the ablation season, for water resource assessment purposes and redrilling of the stakes when necessary. (nichols.edu)