John O'Leary, author of The Times Good University Guide, which comes out tomorrow, answers your questions about applying to university. To post a question write to timeseducation@thetimes.co.uk.

How should I choose my five universities?

Most people decide on a subject before they choose a university, but you have to be confident about both. You may want to be near (or not too near) home, you may want the liveliness of a big city or the community feel of a campus university. Try to visit as many as you can, but you will have to rely on university prospectuses and websites - with a reality check from guides like this one - to get a feel for the rest.

The 61 subject tables in The Times Good University Guide are a starting point, while the main table will give you an idea of where a university stands in the pecking order of higher education. When it comes to getting a job, employers are more likely to be aware of a university's overall ranking than particular subject strengths - except in specialist fields like engineering.

When it comes to narrowing your options down to the final five, try to include an 'insurance' choice. If all your choices have similar entry requirements, you risk disappointment if your grades are not what you expect. Go for at least one that makes lower offers than the rest - but make sure that it is one that you will be happy to go to if the worst comes to the worst.

How can I decide what to study?

Think what you want out of higher education: is it just about a career, or a passion for a particular subject? A familiar subject from school or college is the safe choice - a degree will allow you to explore it more deeply, but you may also become bored with it if you have simply chosen the one in which you get the best results.

If you like the look of a subject that you haven't taken at school, make sure you have the right skills and that you be interested for three (or four) years. Many students underestimate the mathematical content of degrees in economics or philosophy, for example. And think twice before committing yourself to a narrow specialism - golf course management may sound attractive, but a broader management course will leave you with more options, both during your degree and afterwards.

If the career is your priority, you could consult The Times Good University Guide for average starting salaries for graduates in different subjects. But most graduate jobs are open to applicants from any subject. You will be a stronger candidate with a good degree in a subject that captured your interest than if you are offering a mediocre pass in something that you never really wanted to study.

Do universities inflate their degrees to do better in league tables?

Universities keep a keen eye on how they appear in league tables because they know that applicants are influenced by them. Most are well aware of whether they are out of line with their peers on any of the indicators, but they also know that there are eight measures in The Times guide - more in some other tables - so a marginal increase in one is not going to make a lot of difference.

The number of first-class degrees has risen sharply in the last ten years - and it has made no difference to any university's position because all the league tables use firsts and upper-seconds. The biggest single change was a drop of nearly ten percentage points when Cambridge stopped counting results from the first part of its Tripos in the 2007 guide. It led to a drop of ten points out of 1,000 in Cambridge's overall score and no change of position. Anything a university tried to do to inflate its scores would involve a much smaller shift than that and would have very little effect on the table.

League tables are a convenient scapegoat for degree inflation, but they are not responsible for it. The trend started before they were published and has also been seen in the United States, where the results are not part of league tables.

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