---
title: Inter-Case Features in PPM
type: concept
tags: [ppm, features, inter-case, queueing]
sources: []
created: 2026-04-13
updated: 2026-04-13
---

# Inter-Case Features in PPM

Most [[concepts/predictive-process-monitoring|PPM]] models treat each case in isolation. **Inter-case features** capture the surrounding system state — work-in-progress, resource contention, simultaneously running cases — that materially affect prediction targets like [[concepts/remaining-time-prediction|remaining time]].

## Examples of inter-case features
- **Number of active cases** at the prefix cut-off.
- **Activity-level workload** — cases currently at activity `a`.
- **Resource workload** — cases handled by resource `r`.
- **Queue lengths** per activity / resource.
- **System age** — time since the log started or since last drift.

## Why it matters
Congestion effects make remaining time strongly dependent on current system load; a model unaware of workload underestimates time during busy periods and overestimates during quiet ones.

Seminal treatment: **Senderovich et al. 2017** — *Intra- and inter-case features for predictive process monitoring* ([[sources/2017-senderovich-intra-inter-case]]). Demonstrated significant accuracy gains from inter-case features on benchmark logs.

## Implementation
- Compute workload features per prefix at training and inference time.
- Concatenate with intra-case features before encoding or model input.
- Can be combined with any model family (classical ML, LSTM, Transformer).

## Related
[[concepts/predictive-process-monitoring]] · [[concepts/trace-encoding]] · [[concepts/remaining-time-prediction]]