Sampling Error Calculator
Sampling error is an estimate of the margin by which the true score for your institution on a given item could differ from the reported score. To interpret the sampling error, assume that 60% of your students reply "very often" to a particular item. If the sampling error is +/-5%, then the true population value is most likely between 55% and 65%.
By answering a few specific questions about your institution and your students, you can estimate your sampling error for your NSSE administration and see how oversampling will affect your sampling error. This may help you decide whether or not to oversample your students.