Artificial Intelligence
What phenomenon occurs when a machine learning model learns noise and sample-specific patterns rather than generalizable relationships?
Overfitting
What mathematical concept describes the inability to uniquely recover model parameters from ideal, noise-free observations?
Structural non-identifiability
Which theorem states that sufficiently regular sample averages approach a normal distribution as sample size increases?
Central limit theorem
What bias occurs when earlier diagnosis artificially increases measured survival time without delaying death?
Lead-time bias
Which Canadian poet and classicist won the 2026 Nobel Prize in Literature?
Anne Carson
What training problem occurs when gradients become negligibly small as they propagate through multiple neural network layers?
Vanishing gradients
What mathematical quantity determines the basic reproduction number from the next-generation matrix?
Spectral radius
What statistical phenomenon occurs when an association reverses direction after combining data from different groups?
Simpson's paradox
What bias arises when study participation or analysis conditions on a common effect of two variables?
Collider bias
Which 1944 agreement established the framework that led to the IMF and World Bank?
Bretton Woods
What term describes the agreement between predicted probabilities and observed outcome frequencies?
Calibration
What distribution describes the time between infection in a primary case and infection in a secondary case?
Generation time (or generation interval) distribution
What property describes a Markov chain's ability to reach any state from any other state?
Irreducibility
What epidemiological quantity measures the proportion of positive diagnostic test results that represent true disease?
Positive predictive value
Which African country has three capital?
South Africa
What type of dataset contamination occurs when future information improperly enters model training and inflates predictive performance?
Data leakage
What type of epidemiological model incorporates random fluctuations in transmission and transitions between disease states?
Stochastic model
What measure compares the likelihood of observed data under two competing statistical models?
Bayes factor
What bias occurs when a period during which an outcome cannot occur is incorrectly assigned to an exposure group?
Immortal time bias
Which scientist developed the uncertainty principle in quantum mechanics?
Werner Heisenberg
Which model-agnostic explanation technique uses Shapley values to attribute individual predictions to input features?
SHAP
What bifurcation permits a stable endemic equilibrium to coexist with a stable disease-free equilibrium when R₀ is below one?
Backward bifurcation
What mathematical condition requires the Jacobian of a nonlinear system to have eigenvalues with strictly negative real parts for local asymptotic stability?
Hurwitz stability
What causal inference assumption requires every covariate-defined subgroup to have a nonzero probability of receiving each treatment being compared?
Positivity
Which country contains the world's deepest lake, Lake Baikal?
Russia