✅ Data Science Interview Questions with Answers Part-5

41. Why is data visualization important?
Data visualization helps you understand patterns, trends, and anomalies quickly. It simplifies complex data and supports faster decision-making. Visuals also help communicate insights clearly to stakeholders who do not work with raw data.

42. Difference between bar chart and histogram?
A bar chart compares discrete categories using separate bars. A histogram shows the distribution of continuous data using bins. Bar charts focus on comparison, while histograms focus on frequency and shape of data.

43. When do you use box plots?
Box plots are used to visualize data distribution, spread, and outliers. They help compare distributions across multiple groups and quickly highlight median, quartiles, and extreme values.

44. What does a scatter plot show?
A scatter plot shows the relationship between two numerical variables. It helps identify correlations, clusters, trends, and outliers. It is commonly used during exploratory analysis.

45. What are common mistakes in data visualization?
Common mistakes include using the wrong chart type, misleading scales, cluttered visuals, poor labeling, and ignoring context. These errors lead to incorrect interpretation and poor decisions.

46. Difference between Seaborn and Matplotlib?
Matplotlib is a low-level visualization library that provides full control over plots. Seaborn is built on top of Matplotlib and provides high-level, statistical visualizations with better default styling.

47. What is a heatmap used for?
A heatmap visualizes values using color intensity. It is commonly used to show correlations, missing values, or patterns across large matrices where numbers alone are hard to interpret.

48. How do you visualize distributions?
Distributions are visualized using histograms, density plots, and box plots. These charts help understand spread, skewness, and presence of outliers in data.

49. What is dashboarding?
Dashboarding is the process of creating interactive visual reports that track key metrics in real time or near real time. Dashboards support monitoring, analysis, and decision-making.

50. How do you choose the right chart?
You choose a chart based on the data type and the question being answered. Comparisons use bar charts, trends use line charts, relationships use scatter plots, and distributions use histograms or box plots.

Double Tap ♥️ For Part-6