Model Research is a partnership using computer models and statistical analyses to solve problems in biological research.
Tony Ludlow was formerly head of Statistics and Computing and head of the Biometric Modelling Section at the Forestry Commission Research Division, where he was responsible for developing the Forestry Commission model of the processes of forest growth.
He did his Ph.D. using computer models to understand inhibitory networks of neurons and their role in coordinating behaviour. He worked at Imperial College with John Kennedy F.R.S. in experiments on insect behaviour, and took the lead in analysing and modelling the results of their joint work. The studies helped to show how male moths find a female when she is emmitting sex pheromone while other work focussed on aphid flight and locust walking behaviour. Selected publications
Liz Atkinson (Ludlow) studied biochemistry while employed in research on malaria in Liverpool for six years. She worked for three years at Imperial College on the isoenzymes of the protozoan parasite, Sarcocystis, describing a new species in her studies before taking a research fellowship at Kings College, London where she worked on protein metabolism. Selected publications
Model Research has powerful computing equipment running various programming languages as well as Genstat, GLIM 4, Mathcad, LPA Prolog, DARE P and other scientific software, together with desk-top and web publishing.
Over 30 years modelling a wide range of biological systems.
A complex system has many interacting processes. The art of modelling is to find the most important and include them in sufficient detail, with their interactions. Less important processes must be approximated or left out altogether.
To make these key choices we must talk to experts and find what is known, why the model is needed, and what questions it should answer.
We have used models:
A common thread in these and many other studies has been that models show the consequences of our assumptions.
We will meet you to learn about the questions you are asking and to discuss what is known already. After the preliminary discussion we will write a framework for the modelling project. The framework:
The modelling framework will raise further questions and will need to be extended to take advantage of expert knowledge.
The data needed for building and testing a model must be identified and a strategy for testing devised. Data costs and sources need to be identified and information may come from:
Whatever the source, it is usually necessary to analyse or transform the data before it can be used to build or test a model.
Where there are gaps it may still be useful to build a model and try a range of sensible values to see how much difference they make (sensitivity analysis). How accurately must gaps be filled?
There should be nothing mysterious about a model. Once the framework and data sources are agreed, everyone should have a clear understanding and, in principle, anyone should be able to build it. But we are probably quicker and we use literate programming tools that show the science not the ‘do loops’.
A process model can be tested in dozens of ways. Any of its predicted or intermediate variables can be compared with real life and it could fail because:
In contrast, a regression model may only be rejected if it makes the wrong predictions.
A thorough testing strategy needs to be drawn up as part of the framework and implemented as the model is being built.
Where a model is being built as part of a research effort it is inevitable that lessons will be learned and improvements made while it is being developed. Modifications to the framework will be agreed before changes are made and further work is undertaken.
We provide documentation at every stage:
The following lecture notes are available as PDF files and may take some time to download. The size of each file is given in brackets.
Tony Ludlow has written a number of novel applications in LPA Prolog. Two of these, Environmental modelling and Identifying fungi in culture, are described on the LPA web site: www.lpa.co.uk/ind_inf.htm
More recent essays are in bird identification and genealogy: www.ludlowgenealogy.org
To my surprise, I discovered that my paper The behaviour of a model animal (Ludlow, 1976) is still being cited quite regularly. There are other papers and a Ph.D. thesis on the ‘Model Animal’. The fullest and most recent account is the Thesis, so I have scanned it in and made it available as a .pdf file. The 5th Chapter is a detailed theoretical study of orientation in male moths finding a female emmitting sex pheromone and proof changes were finally made on 5th September 2004.
More details and instructions for downloading are available by clicking on: www.modelresearch.com/science/thesis.
Dr A R Ludlow
7 King’s Road
Hants, GU34 1PZ
Tel/Fax: 01420 83922
Our core business is statistical analysis and modelling complex systems, but the techniques we use can be applied to other projects. All of these services are charged at an hourly rate which will be negotiated for each contract. Additional charges may be necessary if we need to buy or rent special software for a particular project.
Writing a framework usually takes about 2 days.
Discussions before and after the framework document are charged at the normal hourly rate, plus necessary travel expenses.
The framework document will include an estimate of time needed for each stage of the main project.
Where a project involves large amounts of data preparation the charges for data entry will be 75% of the standard rate, subject to the quality of data sheets. Last Update: 2015