Elisabeth Murdoch last night said the phone-hacking scandal has forced News Corp to ask "itself some very significant and difficult questions".

Rupert Murdoch's daughter became the third member of her family – following her father and brother James – to make the MacTaggart lecture at the Edinburgh International Television Festival. But her speech was in stark contrast to one made by her brother in 2009, in which he lambasted the BBC and accused the corporation of a "land grab".

Speaking at the annual industry get-together, she said News Corp was "asking itself some very significant and difficult questions about how some behaviours fell so short of its values". She said "one of the biggest lessons" was the need for "a rigorous set of values based on an explicit statement of purpose".

Ms Murdoch also praised the "mindset of the Olympians" and said TeamGB "have changed how we feel as a nation".