📊 Day 13: Bubble Chart in Python

 

📊 Day 13: Bubble Chart in Python

🔹 What is a Bubble Chart?

A Bubble Chart is an extension of a scatter plot where:

• X-axis represents one variable

• Y-axis represents another variable

• Bubble size represents a third variable

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🔹 When Should You Use It?

Use a bubble chart when:

• Comparing three numerical variables

• Showing relative magnitude

• Identifying patterns and clusters

• You want richer insight than a scatter plot

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🔹 Example Scenario

Suppose you are analyzing:

• Advertising spend (X)

• Sales revenue (Y)

• Market size (Bubble size)

A bubble chart shows:

• Relationship between spend and sales

• Which markets are larger or smaller

• Outliers and clusters at a glance

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🔹 Key Idea Behind It

👉 Position = relationship (X & Y)
👉 Size = magnitude (third variable)
👉 Color (optional) = category or group

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🔹 Python Code (Bubble Chart)

import matplotlib.pyplot as plt
import numpy as np

x = np.random.rand(30)
y = np.random.rand(30)
sizes = np.random.rand(30) * 1000
plt.scatter(x, y, s=sizes, alpha=0.6)
plt.xlabel("X Values")
plt.ylabel("Y Values") 
plt.title("Bubble Chart Example")

plt.show()

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🔹 Output Explanation

• Each bubble represents one data point

• Larger bubbles indicate higher magnitude

• Overlapping bubbles suggest clusters

• Alpha improves visibility of overlaps

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🔹 Bubble Chart vs Scatter Plot

Feature	Bubble Chart	Scatter Plot
Dimensions	3 variables	2 variables
Visual impact	High	Medium
Complexity	Medium	Simple
Use case	Multivariate analysis	Relationship analysis

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🔹 Key Takeaways

• Bubble charts show three dimensions at once

• Excellent for comparative analysis

• Use transparency for clarity

• Avoid overcrowding with too many points