CLASSIFICATION OFSTATISTICAL DATA• According to Nature Quantitative data Qualitative Data• According to Source Primary data Secondary data
CLASSIFICATION OFSTATISTICAL DATA• According to Arrangement Ungrouped data Grouped Data• According to measurement Discrete data Continuous data
PRESENTATION OF STATISTICALDATA• Tabular form Reference purpose or general Special purpose or text• Bar charts Subdivided Multiple• Pie diagram• Time series line graph
PRESENTATION OF STATISTICALDATA• Pareto chart• Histogram• Ogive• Lorenz curve
SOURCES OF DATA Primary Secondary Tertiary Autobiographies Abstracts correspondence Biographies bibliographies descriptions of prior books & papers on a chronologies travel topic classifications diaries literary criticism & dictionaries & literary works interpretation encyclopaedia interviews history & historical criticism directories personal narratives political analyses guidebooks and manuals paintings and reviews of law and population registers photographs legislation statistics essays on morals and ethics analyses of social policy study and teaching material
SAMPLING• It is concerned with the selection of a subset of individuals from within a population to estimate characteristics of the whole population.• Researchers rarely survey the entire population because the cost of a census is too high.• The three main advantages of sampling are that the cost is lower, data collection is faster, and since the data set is smaller it is possible to ensure homogeneity and to improve the accuracy and quality of the data.
METHODS OF SAMPLING• Simple random• Systematic• Stratified• Cluster• Probability proportional to size• Quota sampling• Accidental• Line-intercept• Panel