| name | data-visualization |
| description | Master data visualization with chart selection, dashboard design, Tableau, Power BI, and effective data storytelling. |
Data Visualization
Create effective data visualizations and dashboards that communicate insights clearly and drive decision-making.
When to Use This Skill
- Building dashboards
- Presenting insights
- Executive reporting
- KPI tracking
- Trend analysis
- Comparative analysis
- Geographic analysis
- Time series visualization
Core Concepts
1. Chart Selection Guide
**Comparison**:
- Bar chart: Compare categories
- Column chart: Compare over time
- Grouped/stacked bar: Multiple series
**Trend**:
- Line chart: Show trends over time
- Area chart: Magnitude and trend
- Sparklines: Compact trends
**Part-to-Whole**:
- Pie chart: Few categories (<5)
- Stacked bar: Parts over time
- Treemap: Hierarchical data
**Distribution**:
- Histogram: Frequency distribution
- Box plot: Statistical distribution
- Scatter plot: Correlation
**Geographic**:
- Choropleth map: Regional data
- Symbol map: Point locations
- Heat map: Density visualization
2. Dashboard Design Principles
## KPI Dashboard Layout
+----------------------------------+
| Title: Sales Performance |
+----------------------------------+
| KPI | KPI | KPI |
| $1.2M | +15% | 95% |
| Revenue| Growth | Goal |
+----------------------------------+
| |
| Revenue Trend (Line Chart) |
| [Chart showing 12 months] |
| |
+----------------------------------+
| By Region | By Product |
| [Bar Chart]| [Bar Chart] |
+----------------------------------+
| Filters: Date Range, Region |
+----------------------------------+
**Design Principles**:
1. Most important metric top-left
2. Trend charts show context
3. Filters at top or left
4. Consistent color scheme
5. Clear labels and units
6. White space for readability
Best Practices
- Choose right chart - Match data and purpose
- Simplify - Remove chartjunk, reduce clutter
- Use color purposefully - Highlight, categorize
- Clear labels - Title, axes, legends
- Start axis at zero - Avoid misleading scales
- Mobile-friendly - Responsive design
- Interactive - Filters, drill-down
- Tell a story - Guide viewer's attention
Resources
- Storytelling with Data: Cole Nussbaumer Knaflic
- The Visual Display of Quantitative Information: Edward Tufte
- Tableau Public: Free visualization tool
