Log-Logistic Distribution
A two-parameter continuous distribution for positive event times whose logarithm is logistic; its survival function has a heavy tail, and its hazard may rise and then fall.
Encyclopaedia
Explore comprehensive, evidence-informed explanations of key health economics concepts, including their development, application and relationships to other concepts. Published entries are validated through human expert review.
Concepts, entries and ontology terms
A concept page is a published entry on the wiki. Some concepts also have a full encyclopaedia article. The Health Economics Ontology (HEO) holds every concept, including dictionary terms without an article, so it is larger than the list of published pages. The knowledge graph shows how concepts relate to each other.
Log-Logistic Model
The log-logistic model is a parametric survival model, used in health economics, whose hazard can rise to one peak then fall, giving a long survival tail.
Log-Normal Distribution
A probability distribution in which the logarithm of the variable follows a normal distribution, often used for hazards that rise then fall.
Log-Normal Model
A survival model based on the log-normal distribution, capable of representing a hazard that rises then falls, similar in shape to log-logistic.
Log-Rank Test
The log-rank test is a nonparametric test of whether groups such as trial arms have the same survival curve, widely used for time-to-event outcomes in HTA.
Logarithmic Pool
The logarithmic pool combines several experts' probability distributions for an uncertain model input into one by taking their weighted geometric mean.
Logistic Regression
Logistic regression models the log odds of a yes or no outcome, such as an admission, from patient covariates, giving odds ratios and event probabilities.
Long-Term Care Economics
The study of resources, financing, incentives and outcomes involved in sustained formal and unpaid support for people with ongoing care needs.
Lorenz Curve
The Lorenz curve is a graph of the share of a total, such as health or health spending, held by each cumulative share of people ranked lowest to highest.
Lump-Sum Tax
A lump-sum tax is a tax whose amount no change in the taxpayer's behaviour can alter, the efficiency benchmark for funding health care from taxes.
Marginal Analysis
Marginal analysis compares the extra cost and extra benefit of a small change in a health service, to judge whether expanding or cutting it is worthwhile.
Marginal Cost
Marginal cost is the change in total economic cost caused by producing one additional unit of output at a specified level of activity and over a specified time horizon.
Marginal Cost of Healthcare
The additional cost of providing one more unit of healthcare service, such as treating one further patient.
Marginal Rate of Substitution
The marginal rate of substitution (MRS) is how much money or another good a person would give up for one more unit of health without being worse off.
Market Equilibrium
Market equilibrium is the price and quantity at which demand for a health service, medicine or health worker equals supply, so the market clears.
Market Failure
Market failure occurs when markets do not allocate resources efficiently, as in health care through externalities, unequal information or insurance gaps.
Markov Assumption
The Markov assumption is that the next transition in a state-transition model depends only on the current state and model time, not on earlier history.
Markov Chain
A Markov chain is a random process moving between states in which the next state depends only on the current state. It underlies Markov cohort models.
Markov Chain Monte Carlo
Markov chain Monte Carlo (MCMC) is a set of simulation methods that draw correlated samples from the posterior of a Bayesian health economic model.
Markov Cohort Model
A Markov cohort model is a health economic model that moves a hypothetical cohort between health states each cycle to estimate expected costs and QALYs.