American author Mark Twain may have lived in a different technological era but his quote, "There are lies, damned lies and statistics", is very relevant when considering the mobile market.

The Oireachtas Communications Committee heard evidence yesterday from the two big industry players, Vodafone and O2, which together hold 96 per cent of the Irish mobile market.

Unsurprisingly, both mobile phone firms rejected allegations from the Consumers Association of Ireland that they were "ripping off" consumers. They also disputed the regulator's statistics on prices, with Vodafone alleging that ComReg has an agenda to over-regulate the mobile market.

Both firm's management made glossy presentations to the committee, stuffed full of bar charts, graphs and graphics all designed to prove their case: that Irish people talk more on the mobiles than other Europeans, thereby justifying the huge profits generated from the firm's subscribers.

In what was billed by Vodafone as a major concession, it disclosed for the first time that its subscribers use their mobiles for 183 minutes per month for both outgoing and incoming calls. But Vodafone didn't see fit to give us any comparable data for the rest of its European operations for reasons of "commercial sensitivity".

Neither did Vodafone reveal the average per minute price of a contract or pre-paid mobile call despite the protestations of the chairman of the committee. This is hardly a good way to persuade people that its charging strategies are simple and transparent.

In fairness, O2 has produced comparable figures for their European firms that do show Irish people use their phones more. O2 Ireland users use their phones for 188 minutes every month for just outgoing calls.

This is 79 minutes more than its German firm, probably due to Ireland's younger population and a weak German unit.

But perhaps the statistics don't tell the whole story. Vodafone told the Committee its average minutes-per-user figure represented both outgoing and incoming calls. O2's average user figures, which were very similar to Vodafone's, said they represented only outgoing calls made and charged to the subscriber.

So whose figures should the consumer believe?

In fact most of the presentations to the Committee by the regulator and the main mobile firms have highlighted statistics from a single source - a report by the consultancy Teligen for the OECD.

But presentations have often arrived at very different conclusions on the key question of whether call prices are too high.

This begs the question: if the mobile companies and the regulators cannot interpret the pricing data in a simple and conclusive manner, how can the consumer?

Both O2 and Vodafone say about 70 per cent of their subscriber base use pre-paid phones despite the extremely high usage figures in the Republic.

However, billed services tend to be more economical for heavy users, implying that hundreds of thousands of mobile users are paying more than they should have to.

Trying to compare the bewildering number of contract packages on offer from firms is almost impossible, as both Vodafone and O2 as much as admitted at yesterday's Oireachtas meeting.

Other big issues have also not been adequately explained yet by the two big mobile firms, particularly roaming charges levied on people when they travel abroad.

Both firms will have to try a lot harder to convince the public and their representatives that they are offering a transparent and cost-effective service.

Otherwise, when new competitors, Eircom and "3", enter the market next year, they will chose to bring their business elsewhere.