http://manuals.pqstat.pl/ 2026-04-10T18:20:07+00:00 http://manuals.pqstat.pl/ http://manuals.pqstat.pl/lib/tpl/dokuwiki/images/favicon.ico text/html 2022-02-11T10:54:10+00:00 Anonymous (anonymous@undisclosed.example.com) http://manuals.pqstat.pl/en:statpqpl:niezbliczpl:marginpl Sample size determination For the margin of error of the proportion and the mean Since it is usually neither practical nor possible to study the entire population, a subset of it - the sample - is chosen. The sample is of course correspondingly smaller than the population, but it should reflect it well. One of the key aspects in planning a study, besides the randomness of the sample, is the assumption of its size. The size should be chosen so that the inference about the population is true. text/html 2022-02-11T10:55:41+00:00 Anonymous (anonymous@undisclosed.example.com) http://manuals.pqstat.pl/en:statpqpl:niezbliczpl:moclicznpl Power and sample size for test The window with the test power settings and the required sample size for this test is opened with menu Advanced Statistics→Test power and sample size→Power and sample size for test. Power analysis is directly related to testing hypotheses, and therefore to specific statistical tests. Tests vary in their power. Some tests are stronger, others weaker. Because of this fact, if there are several tests available to solve a given statistical problem, it is better to …