A number of books have been written on Bollywood icon Amitabh Bachchan but Susmita Dasgupta's "Amitabh - The Making of a Superstar" is probably the first to analyse the sociological impact of his popularity.

"It's a work that investigates the sociological causes of Amitabh Bachchan's popular appeal - how Bachchan is related to the history of the period of his times and what the sociological dynamics were behind the growth of his image," Susmita told .

Susmita is a deputy chief economist with the economic research unit of the ministry of steel. The author spent almost 16 years researching on Bachchan but she is not happy with the actor's current image.

Said Susmita: "I find Amitabh Bachchan very disappointing because he is now compromising on his image. Amitabh seems to be very eager to disassociate himself with his previous image. He makes statements that are self-destroying."

She is also upset with her favourite star for not acknowledging her invite.

"He knows about the book and I sent him an invite. I am very unhappy he didn't acknowledge it."

Susmita's book, formally introduced Thursday, has been on the shelf for two months and has sold about 2,200 copies without any publicity.

"I wrote this book because of two reasons. First, I was a huge fan of Amitabh Bachchan and this was the subject in my command. The other was that while I was doing my Ph.D in sociology, I wanted to do work on living realities.

"I was familiar with Amitabh as a cine-goer, so I chose him. Had I been a cricket fan, I would probably have done something on Sunil Gavaskar. The idea was to do a work on living history."

Susmita started research on this book in 1977.

"I was writing notes on the subject since 1977 - the year I watched 'Sholay' and became an Amitabh fan. But formally I started writing it in 1991."

Susmita is one of the lucky ones to have enjoyed Bachchan's hospitality.

"After I finished my M. Phil, he invited me to his house and hosted me for seven days. During that time he introduced me to the film world, the inside of the film world and that is how I got inputs for my Ph.D."

Sharing one of the anecdotes, Susmita said: "One day Amitabh Bachchan told me, 'Do you know why these youngsters can't beat me? Because they don't have command over language! In films, command over language is not about delivering dialogues. Even when you sit still, command over the language should show'."

According to Sushmita, there's a clever trick behind his popularity.

"The trick is that he played the roles of huge individuals. If you see, Anil Kapoor is equally suited in his times but he appears as an insignificant actor because he played insignificant roles in his films."

Sushmita feels that another notable quality in Bachchan is that he is a big star but hugely interested in common people.

"When I stayed with him I realised he was as much a fan of me as I was of him. When he used to sit in the 'Kaun Banega Crorepati' chair and when a common man would come and sit across him ... the way he interacted with them showed that he was extremely intrigued by them. That is his USP. He is our fan in a greater manner than we are of him. It's a reciprocal relationship.

"When I met him in Pratiksha, I found that he is a grand person because his house was so simple, so sparse in décor and he was so simple. He was grand in his simplicity. That huge sparseness, the huge economy of his lifestyle was absolutely grand in its own way.

"But today his spectacles are worth Rs.200,000 and he flashes Reid & Taylor, which he never used to wear in those days - he wore khadi (hand spun cotton). I think these are important changes, which can be a foundation for the future research into a man who just decided to survive. It is very disappointing."