Bar Chart vs Histogram Selection | Dataford Interview Questions

Your question is Bar Chart vs Histogram Selection. Take a moment with it on the right.

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Business Context

StreamCart's analytics team is preparing a dashboard for executives. They need to visualize both customer segment counts and the distribution of order values, and they want to avoid using the wrong chart type.

Problem Statement

Explain the difference between a bar chart and a histogram, then use the data below to determine which chart is appropriate for each dataset. Also quantify the order-value distribution so your recommendation is grounded in the data rather than only definitions.

Given Data

Dataset A: Customer counts by acquisition channel

Channel	Customers
Paid Search	420
Organic Search	610
Email	275
Referral	190
Social	305

Dataset B: 40 order values in dollars

Order Values
12, 15, 18, 19, 21, 22, 24, 25, 27, 28, 30, 31, 33, 35, 36, 38, 40, 42, 45, 47, 49, 52, 55, 58, 60, 62, 65, 68, 72, 75, 78, 82, 85, 90, 95, 102, 110, 118, 130, 145

Use the following histogram bins for Dataset B: $[0,25), [25,50), [50,75), [75,100), [100,125), [125,150)$ .

Requirements

State the conceptual difference between a bar chart and a histogram.
Identify whether Dataset A should use a bar chart or histogram.
Compute the frequency in each histogram bin for Dataset B.
Calculate the sample mean and sample standard deviation of Dataset B.
Explain whether Dataset B appears discrete/categorical or continuous/distributional, and which chart should be used.
Briefly note one common mistake analysts make when confusing these charts.

Assumptions

Acquisition channels are categorical labels with no numeric continuity.
Order value is a quantitative variable measured on a continuous monetary scale.
For the histogram, values on the left edge are included and right edge excluded, except the last bin which includes 150.