Comments on „Probability vs. Nonprobability Sampling: From the Birth of Survey Sampling to the Present Day” by Graham Kalton

I would like to congratulate Professor Graham Kalton for his significant and inspiring article entitled as "Probability vs. Nonprobability Sampling: From the Birth of Survey Sampling Present Day". The provides an elegant overview history survey sampling, covering purposive approaches that dominated sampling field in early days but from 1940s, at least official statistics, were gradually replaced entirely by probability-based approaches. Today we may be facing a paradigm shift again, direction is opposite. Non-probability-based are becoming viable, if not only option, fields moving towards big data other new sources methodological