We also provide examples where biased estimators outperform their unbiased counterparts or where unbiased versions are simply not available. Finally, we demonstrate the effectiveness of our framework through experimental results that validate our theoretical findings.

Could Ukraine hold a presidential election right now? Will Europe use frozen Russian assets to fund war? How can Ukraine rebuild China ties? 'Ukraine is running out of men, money and time' Putin says Russia believes it will win in Ukraine in New Year's Eve address Russian President Vladimir Putin has said his country believes it will win the war in Ukraine, nearly four years after he launched an invasion of the neighbouring nation, in comments made during his televised annual New Year's Eve address. The Russian leader called on the country on Wednesday to "support our heroes" fighting in Ukraine, where troops have been waging a brutal offensive since February 2022.

Aston Villa boss Unai Emery had an unhappy 18-month spell in charge of Arsenal that ended in 2019, but can he get the better of his old club on Tuesday? After the abuse he took from Arsenal fans, I'd love nothing more than Emery to go back to the Emirates and win, said BBC Sport football expert Chris Sutton. He absolutely didn't deserve that. Some of those fans should take a long, hard look at themselves for the way they mocked him. I hope Villa go there and spank them, just because of that. Sutton is making predictions for all 380 Premier League games this season, against AI, BBC Sport readers and a variety of guests. For week 19 - which includes the final games of 2025 on Tuesday, 30 December and the first matches of 2026 on New Year's Day - he takes on singer-songwriter Tom A Smith, who is a Sunderland fan.

Ramzan Kadyrov vows retaliation against Ukraine following drone attack on Grozny building, while Ukrainian officials say Zelenskyy remains unafraid of threats.