A spatial distribution in statistics is the arrangement of a phenomenon across the

Earth's surface Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surface ...

and a graphical display of such an arrangement is an important tool in geographical and

environmental statistics Environment statistics is the application of statistical methods to environmental science. It covers procedures for dealing with questions concerning the natural environment in its undisturbed state, the interaction of humanity with the environmen ...

. A graphical display of a spatial distribution may summarize raw data directly or may reflect the outcome of a more sophisticated data analysis. Many different aspects of a phenomenon can be shown in a single graphical display by using a suitable choice of different colours to represent differences. One example of such a display could be observations made to describe the geographic patterns of features, both physical and human across the earth. The information included could be where units of something are, how many units of the thing there are per units of area, and how sparsely or densely packed they are from each other.

Patterns of spatial distribution

Usually, for a phenomenon that changes in space, there is a

pattern A pattern is a regularity in the world, in human-made design, or in abstract ideas. As such, the elements of a pattern repeat in a predictable manner. A geometric pattern is a kind of pattern formed of geometric shapes and typically repeated li ...

that determines the location of the subject of the phenomenon and its intensity or size, in X and Y coordinates. The scientific challenge is trying to identify the variables that affect this pattern. The issue can be demonstrated with several simple examples:

The spatial distribution of the human population

The spatial distribution of the population and development are closely related to each other, especially in the context of sustainability. The challenges related to the spatial spread of a population include: rapid

urbanization Urbanization (or urbanisation) refers to the population shift from rural to urban areas, the corresponding decrease in the proportion of people living in rural areas, and the ways in which societies adapt to this change. It is predominantly t ...

and population concentration, rural population, urban management and poverty housing, displaced persons and refugees. Migration is a basic element in the spatial distribution of a population, and it may remain a key driver in the coming decades, especially as an element of urbanization in

developing countries A developing country is a sovereign state with a lesser developed industrial base and a lower Human Development Index (HDI) relative to other countries. However, this definition is not universally agreed upon. There is also no clear agreem ...

Regular attenuation Curve & without site effect

The spatial distribution of economic activity in the world

The spatial distribution of the economic activity in the world was examined by mapping the artificial lights at night over 250,000 grid cells, the average area of each of which is 560 square kilometers. It was found that 50% of the variation in this activity can be explained through a system of physical geographic features.

The spatial distribution of the seismic intensities of an earthquake

The seismic intensityies of an

earthquake An earthquake (also known as a quake, tremor or temblor) is the shaking of the surface of the Earth resulting from a sudden release of energy in the Earth's lithosphere that creates seismic waves. Earthquakes can range in intensity, fr ...

are distributed across space with an elementary regularity, so that in towns located close to the

epicenter The epicenter, epicentre () or epicentrum in seismology is the point on the Earth's surface directly above a hypocenter or focus, the point where an earthquake or an underground explosion originates. Surface damage Before the instrumental pe ...

of the earthquake, high seismic intensities are observed and vice versa; Low intensities were observed in settlements far from the epicenter. The distance of each settlement from the epicenter is marked with XY coordinates, a variable that affects the seismic intensity observed there. But there are other variables that affect these intensities, such as the geological structure of each settlement, its topography, and more. All these make the simple regularity of the effect of the distance variable more complex. If we succeed in identifying the contribution of most of the variables to the fact that Intensity Z occurred in the XY settlement and not other one, we will understand the pattern that stands behind the organization of the seismic intensity in a specific earthquake, a fact that will help us in the field of seismic risks surveys and their assessments.

The spatial distribution of a population with health impairments related to vitamin A deficiency

Vitamin A Vitamin A is a fat-soluble vitamin and an essential nutrient for humans. It is a group of organic compounds that includes retinol, retinal (also known as retinaldehyde), retinoic acid, and several provitamin A carotenoids (most notably ...

deficiency is a major

public health Public health is "the science and art of preventing disease, prolonging life and promoting health through the organized efforts and informed choices of society, organizations, public and private, communities and individuals". Analyzing the det ...

problem in poor societies. Dietary consumption of foods rich with vitamin A was low in

Ethiopia Ethiopia, , om, Itiyoophiyaa, so, Itoobiya, ti, ኢትዮጵያ, Ítiyop'iya, aa, Itiyoppiya officially the Federal Democratic Republic of Ethiopia, is a landlocked country in the Horn of Africa. It shares borders with Eritrea to the ...

. In 2021, a study was published that evaluated the spatial distribution and the spatial variables affecting it in dietary consumption of foods rich (or poor) in vitamin A among children aged 6–23 months in Ethiopia.{{Cite web , last=Tiruneh, S. A., Fentie, D. T., Yigizaw, T. S., Abebe, A. Gelaye, K. A. , title=Spatial Distribution and Geographical Heterogeneity Factors Associated with Poor Consumption of Foods Rich in Vitamin A Among Children Age 6–23 Months in Ethiopia: Geographical weighted regression analysis , url=https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0252639 , website=PLOS ONE, June, 2021

More examples

*Many police departments colour-code a

city map A city map is a large-scale thematic map of a city (or part of a city) created to enable the fastest possible orientation in an urban space. The graphic representation of objects on a city map is therefore usually greatly simplified, and reduce ...

based on crime statistics. *The

two-step floating catchment area (2SFCA) method The two-step floating catchment area (2SFCA) method is a method for combining a number of related types of information into a single, immediately meaningful, index that allows comparisons to be made across different locations. Its importance lies in ...

has been used to prepare maps showing the relative accessibility of individuals (demand units) to physicians (supply units), by shading which shows many different degrees of accessibility.

Notes

Demographics Spatial analysis Statistical charts and diagrams