What is PopTools?
PopTools is an add-in for PC versions of Microsoft Excel (version 97 and up) that helps with the analysis of matrix population models and simulation of stochastic processes. It was originally written to analyse ecological models, but has much broader application. It has been used for studies of population dynamics, financial modelling, risk analysis, and calculation of bootstrap and resampling statistics.
When installed, PopTools adds a new menu item to Excel’s main menu (see the slightly outdated screenshot), and also adds over a hundred new worksheet functions. The routines include array formulas for matrix decompositions (Cholesky, QR, singular values, LU), eigenanalysis (eigenvalues and real eigenvectors of square matrices) and formulas for generation of random variables (eg, Normal, binomial, gamma, exponential, Poisson, logNormal). Many of these functions depend on Jean DeBord’s TPMath library – a Pascal numerical library – which has been compiled into a DLL accessed via Excel.
Also included in PopTools are routines for iterating spreadsheets. These make it possible to run Monte Carlo simulations, conduct randomisation tests (including the Mantel test) and calculate bootstrap statistics. Some facilities are available for function minimisation and parameter estimation using maximum likelihood techniques, and there are a number of auditing and other tools that the author finds useful in his everyday work.
PopTools requires no programming knowledge, but to fully utilise the package you need some knowledge of matrix algebra, and some understanding of probability and statistics. It is therefore most suitable for those who have done some undergraduate statistics.