Data visualization in Data Science: theory and practice
Andrey Lukyanenko
Senior DS @ Careem
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Content
- What is data visualization and why is it useful?
- Classics of data visualization
- Common software for making the plots
- Chart types
- Skills for professional-level visualizations
- What should and shouldn't you do
- Data Visualization for Machine Learning
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Why visualizations are important
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Why visualizations are important
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Tufte
- Maximize data ink-ratio
- Minimize lie factor
- Minimize chartjunk
- Use proper scales and clear labeling
Python. Matplotlib
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Python. Plotly
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import plotly.graph_objects as go
import pandas as pd
from datetime import datetime
df = pd.read_csv('https://raw.githubusercontent.com/plotly/datasets/master/finance-charts-apple.csv')
fig = go.Figure(data=[go.Candlestick(x=df['Date'],
open=df['AAPL.Open'],
high=df['AAPL.High'],
low=df['AAPL.Low'],
close=df['AAPL.Close'])])
fig.show()
Python. Altair
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import altair as alt
from vega_datasets import data
source = data.cars()
alt.Chart(source).mark_circle(size=60).encode(
x='Horsepower',
y='Miles_per_Gallon',
color='Origin',
tooltip=['Name', 'Origin', 'Horsepower', 'Miles_per_Gallon']
).interactive()
R
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library(ggplot2)
ggplot(mpg, aes(displ, hwy, colour = class)) +
geom_point()
Tableau
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D3.js
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Skills
- Data visualization
- Graphical design, interface design, UX
- Storytelling
- Color: Hue, Value/Lightness, Saturation/Chroma, RGB vs CMYK
- Accessibility
- Style guide
Style guide
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Improvements
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Improvements
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Improvements
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Improvements
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Improvements
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Improvements
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Improvements
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Improvements
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- Exploratory vs explanatory, показать то, что важно
- Pie, 3D
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Good examples
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import seaborn as sns
penguins = sns.load_dataset("penguins")
sns.pairplot(penguins, hue="species")
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import shap
explainer = shap.TreeExplainer(model1, X_train)
shap_values = explainer.shap_values(X_train)
shap.summary_plot(shap_values, X_train)
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References
- https://www.anychart.com/chartopedia/usage-type/
- https://gramener.github.io/visual-vocabulary-vega/#
- https://www.python-graph-gallery.com/
- https://raw.githubusercontent.com/Financial-Times/chart-doctor/main/visual-vocabulary/poster.png
- https://textvis.lnu.se/
- https://www.data-to-viz.com/
- https://www.datavisualizationsociety.org/
References
-
https://towardsdatascience.com/data-visualization-in-data-science-5681cbdde5bf
-
https://github.com/Financial-Times/chart-doctor/tree/main/visual-vocabulary
-
https://revealthedata.com/blog/all/navyki-dlya-vizualizacii-dannyh-i-dataviz-inzhenerov/
-
https://docs.google.com/document/d/1SUZ_DXt_WXPlv1IfqlrwTa00S7b3ghJ_2o_W4yE6_UA/edit#
-
https://blog.datawrapper.de/better-charts/
References
-
https://www.kaggle.com/spitfire2nd/enthusiast-to-data-professional-what-changes/
-
https://medium.com/nightingale/style-guidelines-92ebe166addc
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https://www.tableau.com/learn/articles/best-data-visualization-blogs
-
https://boostlabs.com/blog/10-types-of-data-visualization-tools/
-
https://github.com/lutzroeder/netron
References
References
Contacts
Data Visualization talk
By Andrey Lukyanenko
Data Visualization talk
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