Times of Interest (TOIs)
Temporal parameters that define when your analysis should run
Times of Interest (TOIs)
Times of Interest (TOIs) define the temporal parameters for your analysis - when your analysis should run and what time periods to analyze. They answer the "When?" question of the three fundamental questions framework.
What are TOIs?
TOIs are time ranges and temporal cadence specifications that determine:
- Start and end times for analysis
- Temporal grouping (hourly, daily, weekly, etc.)
- Recurrence patterns
- Temporal filtering of input data
TOI Components
Time Range
Defines the overall period for analysis:
- Start time: When the analysis period begins
- End time: When the analysis period ends
- Duration: Can span from hours to years
Temporal Cadence
Defines how to group time within the range:
- Hourly: Analyze each hour separately
- Daily: Group by day
- Weekly: Group by week
- Monthly: Group by month
- Custom: Define specific time intervals
Recurrence Rules
Optional patterns for selective time periods:
- Weekdays only: Monday through Friday
- Business hours: e.g., 9am-5pm
- Specific days: e.g., weekends, holidays
- Custom patterns: Any recurring schedule
Use Cases
Real-Time Monitoring
TOI: Last 24 hours with hourly cadence
- Monitor current conditions
- Track recent changes
- Enable rapid response
Historical Analysis
TOI: Full year with daily cadence
- Identify seasonal patterns
- Track long-term trends
- Perform year-over-year comparisons
Business Hours Analysis
TOI: 30 days, weekdays 9am-5pm only
- Focus on operational periods
- Exclude off-hours noise
- Optimize processing costs
Trend Detection
TOI: 5 years with monthly cadence
- Identify long-term patterns
- Track gradual changes
- Understand seasonal cycles
Temporal Filtering
TOIs enable temporal filtering of input data:
1. Platform identifies all available data
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2. Filters data to only include timestamps within TOI range
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3. Groups data according to temporal cadence
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4. Passes each time group to algorithm
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5. Algorithm processes data for each time period
This ensures:
- Focused analysis: Only relevant time periods processed
- Organized results: Data grouped by meaningful time intervals
- Efficient processing: No wasted computation on excluded times
Parallelization by Time
Time periods can be processed independently, enabling:
- Parallel execution: Multiple time periods processed simultaneously
- Faster results: Reduces total processing time
- Scalable architecture: Distribute workload across containers
Example: Analyzing hourly data for a full day (24 hours) could run 24 parallel computations if all data is available simultaneously.
Combined Parallelization
TOIs work with AOIs for two-dimensional parallelization:
3 AOIs × 24 hours = 72 parallel processing units
This enables:
- Maximum throughput: Process multiple locations and times concurrently
- Flexible scaling: Adapt resources to workload
- Cost efficiency: Complete large analyses quickly
TOI Configuration Examples
Example 1: Recent Activity
Start: 7 days ago
End: Now
Cadence: Daily
Result: 7 daily snapshots of recent activity
Example 2: Business Quarter Analysis
Start: January 1, 2024
End: March 31, 2024
Cadence: Weekly
Recurrence: Weekdays only
Result: ~13 weekly summaries, excluding weekends
Example 3: Hourly Monitoring
Start: Today at midnight
End: Today at 11:59pm
Cadence: Hourly
Result: 24 hourly analyses for the current day
Example 4: Multi-Year Trend
Start: January 1, 2020
End: December 31, 2024
Cadence: Monthly
Result: 60 monthly data points over 5 years
Best Practices
Cadence Selection
- Match to data availability: Don't use hourly cadence if data updates daily
- Balance detail vs. cost: Finer granularity = more processing
- Consider analysis goals: Use appropriate time scale for insights
Time Range Considerations
- Data availability: Ensure data exists for the specified range
- Processing time: Longer ranges with fine granularity take more time
- Cost implications: More time periods = more processing units
Recurrence Patterns
- Business relevance: Focus on operationally meaningful times
- Cost optimization: Exclude irrelevant time periods
- Comparative consistency: Use same patterns for fair comparisons
Creating TOIs
TOIs can be created through:
Elements Application
- Select time ranges using date pickers
- Choose cadence from predefined options
- Configure recurrence rules visually
Elements API
- Define programmatically using the SDK
- Specify ISO 8601 timestamps
- Use flexible recurrence rule syntax
Temporal Data Types
Different data sources have different temporal characteristics:
Satellite Imagery
- Revisit time: Days to weeks between captures
- Best cadence: Daily or weekly
- Considerations: Cloud cover, sensor availability
Device Location Data
- Frequency: Continuous or near real-time
- Best cadence: Hourly to daily
- Considerations: Data density, privacy windows
Aerial Imagery
- Frequency: On-demand or scheduled flights
- Best cadence: As available
- Considerations: Flight schedules, weather
Next Steps
- Define geographic regions with AOIs
- Learn about Algorithms that process temporal data
- Combine into workflows with Analyses
- Execute on specific time periods through Computations
Updated 5 months ago