Where does persistence collide?

In computer science, persistence is the property of data (or an object) outliving the process that created it, surviving beyond program execution by being written to durable storage rather than vanishing when memory is released. Atkinson and colleagues' 1983 An approach to persistent programming argued that persistence should be orthogonal to data type, so any value could outlast the program, shaping persistent object stores and databases. The referent is the durability of data across time and process lifetimes, unrelated to a weather forecast, a population's survival, or a memory trace beyond the shared notion of lasting.[1]

Unit

Whether and how long data survives beyond the creating process

Recovery means

Not applicable

Measured by

Realised through durable storage and recovery guarantees; assessed by whether state is intact after process or system restart

In ecology, persistence is a component of stability: how long a population or community continues to exist, or the probability it avoids extinction over some horizon, as opposed to how fast it recovers from disturbance. Pimm's 1984 The complexity and stability of ecosystems distinguished persistence from resilience, resistance, and variability as separate facets of stability. The referent is the continued existence of a biological system through time, distinct from durable data or an atmospheric forecast.[2]

Unit

The time a population/community persists, or its probability of not going extinct

Recovery means

Persistence concerns continued existence, not the rate of return after disturbance (that is resilience)

Measured by

Estimated from time to extinction, survival probabilities, or the length of unbroken occurrence in records or models

In weather forecasting, the persistence forecast is the simplest baseline prediction: future conditions will equal present conditions ('tomorrow like today'), exploiting the temporal autocorrelation of weather. Wilks's Statistical methods in the atmospheric sciences treats persistence as a standard reference forecast against which genuine forecast skill is judged. The referent is a no-change prediction rule and the benchmark it provides, a methodological construct distinct from data durability, a population's survival, or a lasting memory.[3]

Unit

A no-change forecast carrying the present state forward

Recovery means

Not applicable

Measured by

Used as a skill baseline; its accuracy depends on the temporal autocorrelation of the variable being forecast

In neuroscience and psychology, memory persistence is the continued availability of a stored memory over time (the durability of a trace against forgetting), set against transience, the active loss of memories. Richards and Frankland's 2017 The persistence and transience of memory argued that forgetting is a regulated process and that persistence and transience are balanced to support adaptive behaviour. The referent is how long a memory endures, a property of biological memory, unrelated to durable computer data or a population's survival despite the shared idea of lasting.[4]

Unit

How long a memory trace remains retrievable

Recovery means

Not applicable

Measured by

Assessed behaviourally by retention over delays and, mechanistically, by the stability of the underlying neural changes