Comprehension test.

This article is called ....... It is written by .....

The examiners have added consecutive line numbers in the margin, with, usually, every tenth line being numbered. This is to facilitate references to the text by both examiners and candidates.

Note that there are some mistakes and misprints in the article.

In their preparation candidates should use a spread sheet or some other tool to investigate thoroughly the procedure described in lines ......, and should attempt to verify the results presented subsequently in the article.

Also candidates should bear in mind the following questions which relate to the modelling process:

• What modelling assumptions have the authors made?
• Have they stated these explicitly or are they implied by something the authors have written?
• Are they reasonable assumptions? Would you be happy to make these assumptions or would you make others?
• Do the authors justify the assumptions? If not can you give a justification of them?
• Can you follow the mathematics through from line to line? Have the authors made any mistakes?
• Are the numerical calculations right?
• Can you explain all statements like "it can be shown that ...." or "it follows that ..." or "clearly...."?
• Have the authors attempted to validate the model by comparing with observations? If not can you suggest experiments that could be carried out?
• Do the authors draw valid inferences and conclusions from the work?
• Is sufficient background information to the problem given in the article or is it necessary to find out things from other sources?

You should be able to relate the article to a Modelling Flowchart.