# Mantel correlogram (and periodogram)

This module expects several rows of multivariate data, one row for each sample. Samples are assumed to be evenly spaced in time.

The Mantel correlogram (e.g. Legendre & Legendre 1998) is a multivariate extension to autocorrelation, based on any similarity or distance measure. The Mantel correlogram in PAST shows the average similarity between the time series and a time lagged copy, for different lags.

The Mantel periodogram is a power spectrum of the multivariate time series, computed from the Mantel correlogram (Hammer 2007).

The Mantel scalogram is an experimental plotting of similarities between all pairs of points along the time series. The apex of the triangle is the similarity between the first and last point. The base of the triangle shows similarities between pairs of consecutive points.

#### References

Hammer, Ø. 2007. Spectral analysis of a Plio-Pleistocene multispecies time series using the Mantel periodogram. *Palaeogeography, Palaeoclimatology, Palaeoecology* 243:373-377.

Legendre, P. & L. Legendre. 1998. Numerical Ecology, 2nd English ed. Elsevier, 853 pp.