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Synthetic Data

Synthetic data can be useful for testing, education, prototyping, and some modeling workflows. It is not automatically anonymous, safe, or useful.

Memorization Detection

Field Card
Problem How do we detect memorization in synthetic data?
The itch Generators can copy rare records, outliers, or sensitive combinations while still producing data that looks synthetic.
Why it matters A public release can expose people, companies, or sensitive events.
Current workaround Run nearest-neighbor checks, spot-check samples, or rely on the generator type.
Why the workaround is insufficient Simple checks miss semantic copying, rare subgroup leakage, and adaptive attackers.
What good progress would look like A practical memorization test suite with multiple attacks, subgroup analysis, and release-review thresholds.
Difficulty Medium
Good for Privacy engineer, ML researcher, benchmark maintainer
Related PETs Synthetic data, DP
Possible first contribution Evaluate three memorization tests on a public dataset with injected rare records and report which tests catch them.

Downstream Utility Measurement

Field Card
Problem How do we measure whether synthetic data is useful for downstream tasks?
The itch Teams report distribution similarity, but users care whether the synthetic data supports specific analysis, testing, or model training.
Why it matters Low-utility synthetic data wastes time and can mislead product, policy, or science decisions.
Current workaround Compare summary statistics or train one model on synthetic data.
Why the workaround is insufficient It misses task-specific utility, rare groups, causal structure, and failure under shift.
What good progress would look like Utility evaluations tied to intended use, with explicit tasks, unacceptable failures, and subgroup reporting.
Difficulty Good first research problem
Good for ML researcher, benchmark maintainer, domain expert
Related PETs Synthetic data, DP synthetic data
Possible first contribution Build a task card for one synthetic dataset release that defines allowed uses and three utility tests.

Residual Privacy Risk Communication

Field Card
Problem How do we communicate residual privacy risk to non-experts?
The itch "Synthetic" sounds safe, while "DP synthetic" sounds formally safe even when utility and parameters matter.
Why it matters Data users, legal teams, and executives may overtrust releases.
Current workaround Add generic caveats in documentation.
Why the workaround is insufficient It does not say what attacks were tested, what failed, or what users must not do.
What good progress would look like A synthetic-data release card that states privacy method, tests, residual risks, intended uses, and prohibited uses.
Difficulty Good first research problem
Good for Privacy engineer, policy researcher, technical writer
Related PETs Synthetic data, DP
Possible first contribution Rewrite an example synthetic-data release note with explicit privacy tests, utility limits, and misuse warnings.

DP Synthetic Data Under Utility Pressure

Field Card
Problem How can teams avoid weakening DP synthetic data claims when utility is poor?
The itch When DP noise hurts utility, teams may tune, rerun, or release supplemental information until the privacy story becomes unclear.
Why it matters Composition and selection effects can quietly invalidate the intended guarantee.
Current workaround Choose a more permissive budget or release non-DP helper artifacts.
Why the workaround is insufficient It hides the privacy cost of iteration and auxiliary releases.
What good progress would look like A release workflow that tracks privacy budget, tuning decisions, auxiliary outputs, and final utility.
Difficulty Medium
Good for Privacy engineer, ML researcher
Related PETs DP, synthetic data
Possible first contribution Document a DP synthetic-data tuning loop and account for every release decision, including failed candidates.