The notebook index
Earlier notes
Earlier reference notes remain available at their existing addresses. The current blog concentrates on programming languages, protocols and self-hosted software.
310 notes.
- What Makes a Public Dashboard Trustworthy?
Trust comes from making a metric’s origin, timing, coverage, units, and limitations visible where people use it.
- How Should a Dashboard Signal Stale Data?
A useful freshness signal defines when data becomes delayed, gives the last successful update, and explains what readers can still rely on.
- Can a Dashboard Explain Missing Values?
Missing data becomes more useful when dashboards distinguish why a value is absent and preserve those distinctions in charts and exports.
- How Do You Choose Useful Dashboard Defaults?
Good defaults answer a common question quickly, while making the selected time range and filters visible and easy to change.
- When Should a Dashboard Show a Range Instead of One Number?
A range can show meaningful uncertainty hidden by estimates, sensor variation, and aggregation—provided the dashboard explains what the endpoints mean.
- How Can Users Compare Readings Across Locations?
Location comparisons are meaningful only when measurement definitions, units, time windows, and reporting coverage align.
- What Should an Outage Dashboard Say During a Feed Failure?
During a feed failure, state what source is affected, when it last worked, what data remains visible, and what is known about the problem.
- How Can a Dashboard Avoid False Precision?
Display only as many digits as the measurement and calculation can support, and explain how aggregation changes a value.
- Which Charts Work for a Small Number of Public Metrics?
Choose a chart around the question—comparison, change over time, or distribution—and keep small datasets easy to read.
- How Should a Dashboard Handle Conflicting Data Sources?
When sources disagree, explain their definitions, timing, coverage, and selection rules instead of blending incompatible values silently.
- What Is a Useful Freshness Indicator for Transit Data?
Transit data freshness concerns when a feed was published or received; scheduled trip times describe planned service and answer a different question.
- How Do You Make a Dashboard Work Without JavaScript?
A useful no-JavaScript baseline puts the essential explanation, current summary, and core data links in the initial page response.
- How Can a Dashboard Make Its Geographic Scope Clear?
Name the places included, make boundaries legible, and identify exclusions so map coverage is not mistaken for universal coverage.
- What Should a Dashboard’s Empty State Explain?
An empty state should identify why the current selection has no results and offer a clear next step without implying a zero reading.
- How Do You Keep Dashboard Filters Understandable?
Filters work best when their labels describe the data, selections remain visible, and readers can remove or reset them easily.
- When Is a Table Better Than a Chart?
Tables are often the clearest choice when readers need precise values, sortable records, or an accessible way to inspect data.
- How Can Dashboards Present Uncertainty Accessibly?
Show uncertainty as part of the result, with visible bounds, plain-language explanations, and labels that remain meaningful without color.
- What Does a Reliable Historical Comparison Require?
Historical comparisons become useful when their periods, definitions, and data coverage are aligned and their differences are made explicit.
- How Should a Dashboard Display Sensor Outages?
Explicit outage markers help readers distinguish missing observations from normal readings and understand the limits of a displayed trend.
- Can a Dashboard Show How a Metric Was Calculated?
A concise method note makes a dashboard metric easier to interpret, reproduce, and compare over time.
- How Do You Test Dashboard Color Choices?
Test contrast and meaning together so readers can interpret a dashboard even when colors are hard to distinguish or unavailable.
- What Should a Dashboard’s Download Button Include?
A useful download preserves the dashboard’s filters and gives the exported records clear fields, units, times, and source context.
- How Can a Dashboard Avoid Misleading Map Interpolation?
Maps should clearly distinguish actual observations from estimated surfaces and explain the method behind any interpolation.
- How Should a Dashboard Compare Scheduled and Actual Service?
Keep planned timetable times distinct from observed service times, and identify the source and time basis of each.
- What Makes a Dashboard Update Notice Useful?
A useful update notice says what changed, what data are affected, when the change applies, and how comparisons may be affected.
- How Can a Dashboard Support Slow Connections?
Prioritize a compact, useful summary and defer large optional assets so readers can understand the data on a slow connection.
- What Should Be Logged When a Public Data Refresh Fails?
Operational logs should make a failed refresh diagnosable while protecting credentials and other sensitive details.
- How Do You Choose a Useful Dashboard Time Zone?
Choose a time basis that suits the reader’s task, state it clearly, and preserve unambiguous timestamps for cross-region comparison.
- How Can Readers Verify a Dashboard Number?
Give readers a direct route from a summary value to its definition, supporting records, and source context.
- What Should a Dashboard Say About Data Coverage?
Coverage notes tell readers which locations, dates, and fields are represented and which gaps or exclusions could affect interpretation.