Professor Robert Caldiani isn't one of these pop psychologists whose work starts and finishes on the daytime TV couch. He's a real academic whose work is based on careful experimentation and published papers.

His idea is that humans react almost unconsciously in fairly predictable, but sometimes odd, ways to social situations.

With his colleagues Dr Noah Goldstein and Steve Martin, he's written a book. Yes! reveals what they call the secrets of the science of persuasion.

They've also recorded a series of podcasts, exclusive to Times Online.

The links below let you download the individual episodes, or you can download them via this RSS feed. If you have Apple's iTunes software installed on your computer, click this link to download the files.

Monday: How to be persuasive by email

Professor Robert Cialdini explains how to be persuasive on email. How a little research can help you get what you want, and why you should always use the Bcc field when asking for help.

Download episode one: How to be persuasive by email

Tuesday: How to persuade on eBay

For researchers, eBay is a huge test-case, and the results they're finding are startling. Professor Cialdini reveals what their research tells us about eBay auction start prices, and how this is transforming how businesses try to change behaviour.

Download episode two: How to persuade on eBay

Wednesday: When less is more

What kind of company tries to sell 26 different varieties of anti-dandruff shampoo? An unsuccesful one. Steve J Martin explains the paradox of choice.

Download episode three: When less is more

Thursday: The power of repetition

Familiarity and similarity are crucially important. Steve Martin tells how simple repetition helped waitresses boost their tips by 70%, and how one man's insight managed to free the South Korean hostages in Afghanistan.

Download episode four: The power of repetition

Friday: The power of favours - why business send Christmas cards

Robert Cialdini explains the science of gifts and favours, and how to harness them to your own advantage.

Download episode five: The power of favours

Yes! 50 Secrets from the Science of Persuasion by Noah Goldstein, Steve J. Martin and Robert B. Cialdini is available now, £8.99 paperback, published by Profile books.. Visit the Yes! website.