Data point
Encyclopedia
In statistics
, a data point is a set of measurement
s on a single member of a statistical population
, or a subset of those measurements for a given individual. In addition, in statistical graphics
, a "data point" may be an individual item with a statistical display; such points may relate to either a single member of a population or to a summary statistic calculated for a given subpopulation.
; so that the type of measurement can specify whether the measurement results in a Boolean
value from {yes, no}, an integer
or real number
, the identity of some category
, or some vector
or array.
The implication of point is often that the data may be plotted in a graphic display, but in many cases the data are processed numerically
before that is done. In the context of statistical graphics
, measured values for individuals or summary statistics for different subpopulations are displayed as separate symbols within a display; since such symbols can differ by shape, size and colour, a single data point within a display can convey multiple aspects of the set of measurements for an individual or subpopulation.
Statistics
Statistics is the study of the collection, organization, analysis, and interpretation of data. It deals with all aspects of this, including the planning of data collection in terms of the design of surveys and experiments....
, a data point is a set of measurement
Level of measurement
The "levels of measurement", or scales of measure are expressions that typically refer to the theory of scale types developed by the psychologist Stanley Smith Stevens. Stevens proposed his theory in a 1946 Science article titled "On the theory of scales of measurement"...
s on a single member of a statistical population
Statistical population
A statistical population is a set of entities concerning which statistical inferences are to be drawn, often based on a random sample taken from the population. For example, if we were interested in generalizations about crows, then we would describe the set of crows that is of interest...
, or a subset of those measurements for a given individual. In addition, in statistical graphics
Statistical graphics
Statistical graphics, also known as graphical techniques, are information graphics in the field of statistics used to visualize quantitative data.- Overview :...
, a "data point" may be an individual item with a statistical display; such points may relate to either a single member of a population or to a summary statistic calculated for a given subpopulation.
Discussion
The measurements contained in a data point are formally typed, where here type is used in a way compatible with datatype in computingComputing
Computing is usually defined as the activity of using and improving computer hardware and software. It is the computer-specific part of information technology...
; so that the type of measurement can specify whether the measurement results in a Boolean
Boolean logic
Boolean algebra is a logical calculus of truth values, developed by George Boole in the 1840s. It resembles the algebra of real numbers, but with the numeric operations of multiplication xy, addition x + y, and negation −x replaced by the respective logical operations of...
value from {yes, no}, an integer
Integer
The integers are formed by the natural numbers together with the negatives of the non-zero natural numbers .They are known as Positive and Negative Integers respectively...
or real number
Real number
In mathematics, a real number is a value that represents a quantity along a continuum, such as -5 , 4/3 , 8.6 , √2 and π...
, the identity of some category
Category
Category, plural categories, may refer to:-Philosophy:*Category of being*Categories *Category *Categories *Category *Stoic Categories-Mathematics:* Category * Abelian category...
, or some vector
Vector space
A vector space is a mathematical structure formed by a collection of vectors: objects that may be added together and multiplied by numbers, called scalars in this context. Scalars are often taken to be real numbers, but one may also consider vector spaces with scalar multiplication by complex...
or array.
The implication of point is often that the data may be plotted in a graphic display, but in many cases the data are processed numerically
Data processing
Computer data processing is any process that a computer program does to enter data and summarise, analyse or otherwise convert data into usable information. The process may be automated and run on a computer. It involves recording, analysing, sorting, summarising, calculating, disseminating and...
before that is done. In the context of statistical graphics
Statistical graphics
Statistical graphics, also known as graphical techniques, are information graphics in the field of statistics used to visualize quantitative data.- Overview :...
, measured values for individuals or summary statistics for different subpopulations are displayed as separate symbols within a display; since such symbols can differ by shape, size and colour, a single data point within a display can convey multiple aspects of the set of measurements for an individual or subpopulation.