Technical practice
How would you structure an open-source Python library for model analysis so others can extend and test it?
What to coverPreparation suggestion: Discuss modular interfaces, tests for numerical behavior and edge cases, and documentation with reproducible examples. Explain how packaging, Git reviews, and CI checks would help collaborators maintain the library.
How would you diagnose a PyTorch model whose training loss falls but validation performance deteriorates?
What to coverPreparation suggestion: Distinguish overfitting from data leakage or evaluation errors using learning curves, split checks, and a verified evaluation mode. Explain which controlled change you would test first and what result would support your diagnosis.
How do attention, positional information, tokenization, and training objectives shape transformer behavior?
What to coverPreparation suggestion: Explain each component and compare, for example, masked-language modeling in BERT with autoregressive prediction in GPT-style models. Discuss how those choices affect an experiment or interpretation of its results.
How would you evaluate an explanation method across text, image, and tabular models?
What to coverPreparation suggestion: Choose relevant methods named in the posting, such as SHAP, integrated gradients, or Grad-CAM, and explain where each is applicable. Discuss faithfulness checks, sensitivity to baselines or perturbations, and why a plausible-looking explanation is not proof of causality.
How would you use activation patching to investigate a model failure?
What to coverPreparation suggestion: Describe a controlled pair of inputs, the activation intervention, and a measurable change in output. Address confounding effects and what additional tests would be needed before claiming a circuit explains the behavior.
How would you benchmark uncertainty estimates alongside model robustness?
What to coverPreparation suggestion: Compare a stated approach such as an ensemble, Bayesian method, or test-time augmentation against an appropriate baseline. Discuss calibration, performance under distribution shift, computational cost, and how you would avoid drawing conclusions from a single metric.
If assigned to tabular foundation models or TabTune, how would you test whether a proposed improvement helps?
What to coverPreparation suggestion: Define representative tabular tasks, strong baselines, consistent splits, and an ablation of the proposed change. Discuss predictive performance alongside runtime or resource use, without assuming a particular architecture or dataset is required.
If assigned to RL fine-tuning for alignment, how would you evaluate a proposed algorithmic change?
What to coverPreparation suggestion: State the objective, baseline, and observable measures of desired behavior, then describe controlled comparisons and failure checks. Discuss reward misspecification and the trade-off between apparent gains and training cost.
When would you choose LoRA or adapters rather than full-model fine-tuning?
What to coverPreparation suggestion: Compare trainable parameters, memory, adaptation flexibility, and possible quality differences. Explain how you would evaluate the choice for an instruction-tuning or domain-specialization task; these are preferred areas, not duties guaranteed for every intern.
How would you design a systematic study that could support a research paper or technical report?
What to coverPreparation suggestion: Define a falsifiable question, baselines, ablations, metrics, and a reproducible experiment record. Explain how you would handle negative results and separate observations from claims the evidence does not support.
Behavioural practice
Tell me about a time you collaborated across research and engineering on a technical problem.
What to coverPreparation suggestion: Use a real situation, your specific coordination or implementation actions, and the result. Show how you reconciled research goals with engineering constraints rather than claiming sole ownership of a team outcome.
Describe a time a code review changed your approach.
What to coverPreparation suggestion: Give the situation, the feedback received, the action you took, and the result. Focus on how the change improved correctness, testability, or maintainability.
Tell me about a study whose results did not support your initial hypothesis.
What to coverPreparation suggestion: Explain the question, how you checked the experiment and investigated alternatives, and what you concluded. Include how you communicated uncertainty or negative findings to others.
Describe a time you explained a complex ML result to collaborators with different technical backgrounds.
What to coverPreparation suggestion: Identify the audience and decision at stake, the explanation or written material you produced, and the result. Show how you distinguished evidence, limitations, and open questions.
Tell me about a time you took initiative on an ambiguous technical task.
What to coverPreparation suggestion: Describe the ambiguity, how you set a tractable scope or sought input, what you did, and the result. Relate your example to reliable progress without implying a particular Lexsi Labs workflow.