Where does spread collide?

In finance, a spread is the difference between two prices or rates quoted at the same moment: most narrowly the bid-ask spread, the gap between the highest price a buyer will pay and the lowest a seller will accept, but the word also names a yield spread between two bonds or a credit spread over a benchmark rate. Amihud and Mendelson's 1986 Asset pricing and the bid-ask spread treated the bid-ask spread as a cost of trading for which investors demand compensation, so that less liquid assets carry higher expected returns. The referent is a monetary gap between two quoted figures, measured in currency or basis points, not the dispersion of a distribution, the transmission of an infection, or a handicap set for a wager.[1]

Unit

A gap between two quoted prices or rates, in currency or basis points

Recovery means

Not applicable; a spread widens or narrows with market conditions rather than recovering

Measured by

Read off a quote as the difference between the bid and the ask, or between two yields, and tracked in currency units or basis points

In statistics, spread, also called dispersion or scale, is the extent to which the values of a distribution are stretched out around their centre: it is what the range, the variance, the standard deviation, and the interquartile range each try to summarise, distinct from the location, or central tendency, of the same distribution. Bickel and Lehmann's 1976 Descriptive statistics for nonparametric models. III. Dispersion set out formal requirements that any coherent measure of spread should satisfy and studied estimators that meet them. The referent is a property of a set of numbers, describing how widely they vary, and it has nothing to do with a price gap, the spread of a disease, or a betting handicap.[2]

Unit

The width of a distribution around its centre, in the units of the variable or their square

Recovery means

Not applicable

Measured by

Summarised by the range, variance, standard deviation, mean absolute deviation, or interquartile range of the observed values

In epidemiology, spread is the transmission of an infectious agent from one host to others through a population over time: a pathogen passes from the infected to the susceptible by contact, droplets, vectors, or other routes, and the epidemic grows or fades depending on how fast this happens. Kermack and McKendrick's 1927 A contribution to the mathematical theory of epidemics gave the compartmental model in which susceptible, infected, and recovered fractions change over time, and derived the threshold that decides whether an outbreak spreads or dies out. The referent is a dynamic process of transmission among living hosts, tracked by case counts and reproduction numbers, not a gap between prices, the dispersion of a distribution, or a wager's handicap.[3]

Unit

The passage of an infection through a population over time, tracked by case counts

Recovery means

Hosts leave the infectious pool by recovering or being removed, which slows further transmission

Measured by

Tracked by incidence and prevalence counts and summarised by the reproduction number that governs whether cases grow or decline

In sports betting, the spread, or point spread, is a handicap the bookmaker assigns to the favourite so that a bet on either side is roughly an even proposition: the favourite must win by more than the spread to cover it, and bettors wager against that adjusted margin rather than the raw result. Levitt's 2004 Why are gambling markets organised so differently from financial markets? examined how bookmakers set point spreads, arguing they are chosen to exploit bettor biases and maximise profit rather than simply to balance the money wagered on each side. The referent is a number set for a wager on a game's margin of victory, quoted in points, and it is unrelated to a price gap, a distribution's dispersion, or the spread of a disease.[4]

Unit

A handicap on a game's margin of victory, quoted in points

Recovery means

Not applicable

Measured by

Posted by bookmakers as a number of points and settled after the game against the favourite's actual margin of victory

In disability studies, spread refers to the tendency for one disabling characteristic to colour how a person is judged as a whole. This meaning comes from Wright (1960) in Physical disability.[5]

Unit

Recovery means

Measured by