PV115 April 20211
Correlation and matplotlib.animation
Katarína Švecová
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Correlation
̶  Dependence
̶  Statistical relationship between two random variables
̶  Linear correlation (Pearsons correlation coefficient)
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Variance, Covariance
̶  E is expected value
(average)
̶  µ too
̶  corr(X,Y)= cov(X,Y)/
√(var(X)*var(Y)
https://en.wikipedia.org/wiki/Covariance
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Pearsons correlation coefficient
̶  σ= √var (rozptyl= √štandardnej
odchýlky)
̶  Linear correlation of numerical
variables
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https://en.wikipedia.org/wiki/Correlation_and_dependence
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Pearsons correlation coefficient illustration
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https://en.wikipedia.org/wiki/Correlation_and_dependence#/media/
File:Correlation_examples2.svg
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Other correlation measures
̶  Spearman correlation coefficient
̶  Pearson coefficient between rank variables
̶  Asseses monotonic correlation
̶  Kendall rank correlation coefficient
̶  Point biserial for one binary variable
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https://en.wikipedia.org/wiki/Kendall_rank_correlation_coefficient
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scipy.stats
̶  Big library with a lot of statistical functions
̶  For correlation:
̶  scipy.stats.pearsonr(x, y)
̶  scipy.stats.spearmanr(x, y)
̶  scipy.stats.kendalltau(x, y)
https://realpython.com/numpy-scipy-pandas-correlation-python
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Matplotlib
̶  A python library for plots
̶  Simple plot, subplots, images, heatmaps, histograms, 3d…
̶  Animations
̶  Examples:
https://matplotlib.org/stable/tutorials/introductory/sample_plots.html
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Matplotlib
̶  Simple example
https://matplotlib.org/stable/gallery/lines_bars_and_markers/simple_plot.html
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Matplotlib.animation
̶  Live animations
̶  Example from
https://matplotlib.org/2.0.2/examples/animation/simple_anim.html
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Open in pycharm
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Bar Chart Race
̶  Built on matplotlib.animation
̶  Works on 3-dimensional data
̶  Example from https://pypi.org/project/bar-chart-race/