A new YouGov Profiles analysis of almost 4,000 public figures reveals that Vladimir Putin was the person with the biggest improvement in reputation in 2015 among British people - although he remains mostly disliked

On July 17 2014 a passenger plane flying over Ukraine was shot down killing all 238 passengers. A final report said the airliner was brought down by a Buk surface-to-air missile launched from Eastern Ukraine, launched by pro-Russian forces according to the US. Russian President Vladimir Putin blamed the Ukrainian government, but this looked like a man who was crumbling. Even as late as August 2015, pundits sensed a putsch was underway to oust the troubled leader. Then on September 30 2015 Russia began bombing Syria. At first the US was horrified – it claimed Russia was indiscriminately attacking rebels, including American-backed forces – but it soon became clear Putin was shaping the narrative, and Western opposition to Assad was temporarily suspended.

A new YouGov Profiles analysis reveals that at exactly the time Russia began its bombing campaign in Syria, Putin's ratings shot up. He now has the most improved rating of any person YouGov collects reputation data on, and is the third most improved out of over 3,000 analysed.

The improvement score has been calculated by subtracting the average positivity of the last 300 ratings for an entity in 2015 from the first 300 ratings in 2015, for any person that has had at least 1,200 ratings throughout the year.

3,371 entities qualified for the analysis and these have been divided into the eight groups which showed the most significant and interesting movements over the course of the year. In the public figures group led by Vladimir Putin, other big movers are a number of Liberal Democrat politicians, likely attracting sympathy after the party's heavy defeat in May, as well as two risers in the Labour Party. Dan Jarvis, tipped as a potential future leader had a rise from relative obscurity, and Sadiq Khan – Labour's candidate for the 2016 London Mayoral election – also had a good year.

Unfortunately for the opposition seven of the ten public figures who lost the most ground are Labour MPs – including the leader and shadow chancellor.

2015's biggest winners and losers Numbers show the difference between the average positivity of the first and last 300 ratings in 2015 for things with over 1200 ratings this year. All data from YouGov member's Profiles

Choose a group to see how they fared in 2015

Irish singer-songwriter Hozier, whose September 2014 album reached number three in the UK charts, saw the biggest increase in positivity of any thing in the analysis. Married at First Sight, the TV programme claiming (successfully, for one couple at least) to find true love purely through science, was the second biggest climber, starting with low ratings in the first episode and climbing quickly by the final show. Match of the Day, Eastenders, Come Dine with Me and Britain's Got Talent are among the biggest TV programme sufferers over the course of the year however.

Pop punk act Fallout Boy and Justin Bieber saw big improvements in their scores, and Bieber's is particularly notable for coming from a lower score than Putin (the data is of over-18s, making any improvement in scores for acts with a primarily young audience impressive).

After throwing out George Osborne's tax credit cuts bill, the House of Lords enjoyed the largest boost of any institution – bigger even than the RAF. And after an unexpected run of victories in the Premier League Leicester City FC saw a huge increase in positivity of +30 points, bigger than the England Cricket team's +20 point increase for winning the Ashes in August.

That's the yearly round-up, but feel free to explore the data in the table above and visit the pages of any of the people or things mentioned by searching the YouGov website. On the pages you'll find line charts showing shifts in opinion throughout the year, and if you log in you can even contribute your own ratings and opinions. Happy 2016.