LoopAnalyst (version 1.1-1)

make.T: Compute the Absolute Feedback Matrix of a Community Matrix

Description

Validates a community matrix and computes its absolute feedback matrix.

Usage

make.T(CM, status=FALSE)

Arguments

CM

A valid community matrix.

status

Switches on an element-by-element progress indicator when set to TRUE. Set to FALSE by default.

Value

• The absolute feedback matrix for a community matrix

Details

The supplied matrix is validated as a community matrix, and its absolute feedback matrix is computed. The value of a given element indicates the total number of disjoint cycles spanning all varibles of the complementary subsystem for each path from j to i. Values of a given element may be positive or zero, and bounds the magnitude of the associated adjoint matrix of the negative community matrix. NOTE: weighted feedback, adjoint and absolute feeback matrices are transposed relative to the community effect matrix.

References

Dambacher, J. M., et al. (2003) Qualitative stability and ambiguity in model ecosystems. The American Naturalist, 161(6),876--888

Dambacher, J. M. and Li, H. W. and Rossignol, P. A. (2002) Relevance of community structure in assessing indeterminacy of ecological predictions. Ecology, 83(5),1372--1385

See Also

make.cem, make.wfm, make.adjoint and weighted.predictions.

Examples

## compute T for a community matrix
data(community.matrix)
make.T(community.matrix)