STAT231 Lecture Notes - Lecture 4: Kurtosis, Step Function, Bar Chart
15 Jan 2018
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A note about tq1 will be posted on learn tonight -> up to today"s material (ignore the last question on the sample quiz) Recap: centre -> sample mean, variability -> variance, standard deviation, symmetry -> mean - median, kurtosis -> compare to normal distribution, correlation coefficient: rxy measures association. Summaries: to identify the distribution from which the data is drawn, to find the shape of the data set. The five number summary: minimum, q1, q2, q3, maximum. These five numbers provide the rough shape of the graph. Correlation coefficient measures the linear association between two variables. Histogram: grouped data example: group freq (the cohorts are called bins) Frequency histogram: frequency as y-axis, and bins as x-axis (bar graph) Relative frequency = frequency for the bin / total frequency. The reason why we draw density histogram is that we want to compare our data (shape of graph) with known density functions of distributions.
