statistics Statistics (from German language, German: ''wikt:Statistik#German, Statistik'', "description of a State (polity), state, a country") is the discipline that concerns the collection, organization, analysis, interpretation, and presentation of ...

, a Galbraith plot (also known as Galbraith's radial plot or just radial plot) is one way of displaying several estimates of the same quantity that have different

standard error The standard error (SE) of a statistic (usually an estimate of a parameter) is the standard deviation of its sampling distribution or an estimate of that standard deviation. If the statistic is the sample mean, it is called the standard error ...

It can be used to examine

heterogeneity Homogeneity and heterogeneity are concepts often used in the sciences and statistics relating to the uniformity of a substance or organism. A material or image that is homogeneous is uniform in composition or character (i.e. color, shape, siz ...

in a

meta-analysis A meta-analysis is a statistical analysis that combines the results of multiple scientific studies. Meta-analyses can be performed when there are multiple scientific studies addressing the same question, with each individual study reporting me ...

, as an alternative or supplement to a

forest plot A forest plot, also known as a blobbogram, is a graphical display of estimated results from a number of scientific studies addressing the same question, along with the overall results. It was developed for use in medical research as a means of ...

. A Galbraith plot is produced by first calculating the standardized estimates or ''z''-statistics by dividing each estimate by its

(SE). The Galbraith plot is then a

scatter plot A scatter plot (also called a scatterplot, scatter graph, scatter chart, scattergram, or scatter diagram) is a type of plot or mathematical diagram using Cartesian coordinates to display values for typically two variables for a set of data. ...

of each ''z''-statistic (vertical axis) against 1/SE (horizontal axis). Larger studies (with smaller SE and larger 1/SE) will be observed to aggregate away from the origin.University of York, Department of Health sciences MSc course material
/ref>

References

External links

*Galbraith plots are available within th
metafor
package in R, along with various other diagnostic and summary plots.
MIX 2.0
Software to perform meta-analysis and create Galbraith plots in Excel.
RadialPlotter
Java application for fission track, luminescence and other radial plots from P. Vermeesch.

function within the R package 'numOSL' from Peng Jun for statistical age models analysis in optically stimulated luminescence dating.

function within the R package 'Luminescence' to produce Galbraith plots.

* Galbraith, R.F., 1990. The radial plot: Graphical assessment of spread in ages. International Journal of Radiation Applications and Instrumentation. Part D. Nuclear Tracks and Radiation Measurements, 17 (3), pp. 207–214. . * Galbraith, R. & Green, P., 1990. Estimating the component ages in a finite mixture. International Journal of Radiation Applications and Instrumentation. Part D. Nuclear Tracks and Radiation Measurements, 17 (3), pp. 197–206. * Galbraith, R.F. & Laslett, G.M., 1993. Statistical models for mixed fission track ages. Nuclear Tracks And Radiation Measurements, 21 (4), pp. 459–470. * Galbraith, R.F., 1994. Some Applications of Radial Plots. Journal of the American Statistical Association, 89 (428), pp. 1232–1242. * Galbraith, R.F., 2010. On plotting OSL equivalent doses. Ancient TL, 28 (1), pp. 1–10
PDF on Ancient TL website
* Galbraith, R.F. & Roberts, R.G., 2012. Statistical aspects of equivalent dose and error calculation and display in OSL dating: An overview and some recommendations. Quaternary Geochronology, 11, pp. 1–27. {{doi, 10.1016/j.quageo.2012.04.020 Statistical charts and diagrams Meta-analysis

See also

References

External links

Further reading