The twenty-first century is the Century of Information. Scientifically designed gathering, collation, analyses, interpretation, sharing and dissemination of information have become the primary occupation of millions, as the activity encompasses the widest possible spectrum of subjects ranging from education to development including social sciences, developmental economics and planning, medical sciences, engineering and even commercial subjects such as marketing and branding. The two major pillars in this grand edifice are ‘survey designs’ and ‘evaluation designs’. In spite of the significant potential of statistical designs in the development of valid and reliable information, there is a wide and visible gap between development of theory and its practice.

Professor Leslie Kish, one of the world's top survey statisticians, once commented in his paper ‘The Hundred Years’ Wars of Survey Sampling’, “my central complaint is that over 95% of statistical attention in academia, textbooks and publications is devoted to mathematical statistical analysis and only 2% to design” (Kish, 2003a). With regard to attention to designs, his comment is as apt as ever. This is a rather unfortunate situation, particularly since the two designs can compliment and nurture each other's application and growth. Professor Kish continued to remark “the consequences of that neglect are too often poor designs by non-statisticians (engineers, economists etc.)”. Given this, the present book is a modest attempt to provide practitioners with tools for application of both designs, irrespective of their field of expertise.

A BRIEF HISTORY OF TWO DESIGNS

Understanding the prevalence of variables and their causal relationships has long been the prime focus of research. Initially, the interest was on obtaining a count of the population, such as adult population for tax purposes as well as for enrolment in the military, availability of land for habitation and agriculture etc. Graunt (1662) estimated the population of London around the year 1662. Utilising parish registers, he first estimated the ratio of number of burials per family. In fact, he observed that there would be 3 burials per 11 families in a year. He also obtained the total number of burials in London. With the help of the total and the ratio, he then estimated the total number of families. An assumption about the average family size then resulted in the estimated total population of the country (Bethlehem, 2009). Laplace used a type of survey to estimate the population of France in around the year 1812.