Writing Experiment Sections
1 Why This Page Matters
Many weak experiment sections fail for a simple reason:
they produce results, but they do not answer the paper’s actual claims.
A strong experiment section is not just a collection of tables.
It is a structured argument about:
- what should be compared
- which variables matter
- what counts as success
- which failure cases would change the reader’s trust
2 What An Experiment Section Has To Do
A strong experiment section usually has to do five things clearly:
- say what claim each experiment is testing
- choose baselines that make the comparison meaningful
- use metrics that match the paper’s stated objective
- show enough ablations or sensitivity checks to isolate the mechanism
- report limitations, instability, or failure regimes honestly
If one of those is missing, the section often feels like evaluation theater rather than evidence.
3 The Load-Bearing Parts
3.1 Claim-to-Experiment Matching
Before writing any result table, the paper should know:
- which claim is about accuracy or predictive performance
- which claim is about efficiency or scalability
- which claim is about robustness, calibration, or stability
- which claim is about interpretability, structure, or mechanism
Each experiment should support a claim that the paper has already made.
3.2 Baselines
Baselines should be chosen to make the comparison honest.
The reader should be able to tell:
- why these baselines were selected
- whether they are strong enough to make the win meaningful
- whether implementation details make the comparison fair
Weak baselines can make even a true improvement look suspicious.
3.3 Metrics
Metrics should match the real objective of the paper.
If the claim is about:
- prediction, use predictive metrics
- uncertainty, use calibration or uncertainty metrics
- reconstruction, use reconstruction metrics
- detection or decoding, use error or decision metrics
- efficiency, report runtime, memory, or compute setting clearly
One of the fastest ways to lose trust is to optimize one thing and report another.
3.4 Ablations And Sensitivity Checks
Ablations should answer:
- which component is carrying the gain?
- how sensitive is the result to hyperparameters or design choices?
- does the method still behave sensibly outside the best-case setting?
Without this, the reader often cannot tell whether the proposed mechanism matters or whether the result is fragile.
3.5 Failure Cases
Failure analysis is not optional polish.
It is part of the evidence.
If the paper never shows:
- where performance drops
- where assumptions fail
- which settings are unstable
then the experiment section is probably overstating what was learned.
4 Common Failure Modes
- benchmark tables appear before the reader knows what claim they are meant to test
- baselines are weak, outdated, or badly tuned
- metrics do not match the paper’s stated objective
- ablations are too shallow to isolate the main mechanism
- the section hides variance, instability, or failure regimes
5 A Practical Writing Loop
Before polishing prose, force the section through this loop:
- list the main claims
- assign at least one experiment to each claim
- justify the baseline set in one sentence each
- check whether every reported metric answers a stated objective
- add one explicit failure, limitation, or stress-test subsection
If step 2 or 4 fails, the issue is usually paper design rather than presentation.
6 How This Connects To The Site
- Claim-Evidence Matrix helps map each empirical claim to the evidence it still needs.
- Theorem-to-Experiment Alignment matters when theory and experiments coexist in the same paper.
- Writing Theory Sections is the companion page on the theorem side of the story.