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Univariate statistics summarize variable, detail Measuring central tendency – mean, median Measuring variation – variance, standard deviation other measures Skewness (measures symmetry or lack of it) Skew: right (+) and left (-) Kurtosis (measures peakedness) Modality Unimodal Bimodal Poly- or multimodal Discussion of weighted and unweighted analyses Sample size (N) Problems created by missing data Ways to correct the problem of missing data Problems created by outliers Techniques for identifying outliers Mean, minimum & maximum values Box Whisker plot Stem & Leaf plot Scatterplot Frequencies (f), proportions (p), and percentages (P) Histogram Creating intervals for a measurement variable Optimal number of intervals in a frequency table Assignment #2 Homework Assignment: (1) Choose any reasonably sized and documented dataset (at least 100 observations and at least 10 variables) and prepare it for analysis (create new variables etc.). (2) Discuss the dataset generally (e.g. how large it is) and variables of interest to you specifically. (Due 5/7/04) What is the logic behind the construction of an index or scale? What are their limitations? Understanding relationships between two variables, scatterplots, crosstabs, presentation of data in tables.