Britain's Guardian newspaper says the global economy is poised on a knife-edge and could go either way next year - strong recovery or a return to global recession.

In these volatile and uncertain times, we examine the five main things that will help decide the fate of the world economy in 2015.

1. The wounded Russian bear

A halving in the price of oil, Western sanctions and a collapsing currency saw Russia's economy shrinking for the first time in five years with with GDP in November 0.5 per cent lower than in same month year ago.

Even before the dramatic plunge in the rouble in the weeks running up to Christmas, the Russian central bank was predicting the economy could contract by up to 4.8 per cent next year if the price of oil, which accounts for 70 per cent of the country's exports, fails to recover from five-year lows.

Neil Shearing of Capital Economics says Russia is "staring down the barrel of a deep recession" and how bad it gets will depend on what happens to the price of oil and whether the West lifts its economic sanctions over Russia's backing for separatists in Ukraine.

Why should we care? Because Russia is a third-world economy with first-world missiles.

Political pundits say a failing Russian economy could spur President Vladimir Putin into more aggressive moves abroad.

There are also fears Russia will set off a chain reaction, intensifying the flight to safety as global investors flee from other emerging markets. These markets are already being affected by funds moving back to the United States as the surging dollar gains in anticipation of higher interest rates.

2. Plunging oil prices

Oil prices have tumbled with no imminent end in sight. In July this year, a barrel of Brent crude cost US$115 a barrel. It now goes for just half that price.

The big drop in the price of oil is positive for global growth because it puts more money in the hands of consumers and cuts costs for businesses.

But it is also creating credit stress in countries heavily dependent on oil revenues like Russia, Venezuela and Iran, which can only balance their books if the oil price is at US$100 a barrel or more.

Britain's leading fund manager, Neil Woodford, has warned that falling oil prices could prompt a rout in the global bond market as US shale companies default on the vast debts that have financed the fracking boom, the Guardian reported. From virtually zero five years ago, bonds issued by shale oil companies now make up 15 per cent of all "high-yield" or junk bonds in the US. If drillers default on their US$200 billion in borrowings, it could create a contagion in junk bond markets akin to the sub-prime mortgage collapse.

3. How China fares

It is a given that the world's largest economy will continue to slow in 2015 as it undergoes tough but necessary structural adjustments. The question is by how much?

A sluggish Chinese economy is already affecting the rest of the world in many ways: exports to China, investments from China, the price of oil and other commodities and the threat of deflation.

Some China watchers are betting on a soft landing next year, says MarketWatch. Goldman Sachs, for example, expects growth to moderate to 7 per cent in 2015 from an estimated 7.3 per cent this year as credit tightens and the housing market continues to correct.

"However, we see little risk of outright deflation, with policy makers ready to respond quickly if growth or inflation slows significantly," the Goldman analysts said in a recent note.

The expectation that Beijing will take further steps to boost the economy has sent China's stock market soaring almost 50 per cent this year, making it the best performer among the world's major bourses.

4. US pulling the world

After suffering the worst financial crisis since the Great Depression, the US economy rebounded in 2014. While the housing market is still slow, oil prices are plummeting, the Dow Jones Industrial Average is up 8.5 per cent after climbing above 18,000 points for the first time ever, the unemployment rate has fallen to a six-year low of 5.8 per cent in November, and the economy grew five per cent in the third quarter - the fastest pace in a decade.

Economists say the US now has the momentum to do even better next year. Growth should accelerate in 2015 as higher wages spur more spending, construction and investment. The sharp fall in oil prices will slow energy production but still be a net gain for the economy.

But there are still plenty of risks, including slowdowns in Europe and Asia as well as a possible collapse in the Russian economy. Said CNBC senior analyst and commentator Roy Insana: "The world is slowing down as we are accelerating, so, there could be a bit of a drag on U.S. growth from that."

How fast the US economy grows next year will also shape the Federal Reserve's timetable for raising interest rates from record lows - and this will impact stock markets, currencies and borrowing costs around the world.

5. Eurozone at risk

The eurozone is the crisis that keeps on giving, and there is every reason to believe this will remain the case in 2015, says the Guardian and just about everybody else.

With growth of just 0.2 per cent in the third quarter of this year and inflation at 0.3 per cent at last count in November, the region's recovery has failed to take off. Greece and Spain are stuck in deflationary rut and fears are this will spread to the rest of the region - prices will continue to fall and businesses and consumers will continue to delay spending expecting prices to fall further. Falling oil prices feed into this deflationary spiral.

Measures announced in 2014, including charging banks to park cash with the ECB in a bid to encourage more lending, have failed to provide a silver bullet. There is one weapon left - full-blown quantitative easing, or QE, a la the US Fed. Germany has strongly opposed the massive buying of gvernment bonds to boosr the eurozone economy with cheap money but more bad economic data in 2015 could override it.

To stir the pot, polticial turmoil has once again put Greece back on centre stage, re-enacting a drama played in the darkest days of the 2012 European debt crisis. Lawmakers this week failed to endorse a new president, forcing the government to call a snap election for next month. There are fears the hard-left Syriza party will win and reverse austerity policies required under an international bailout of the country, putting that at risk. Prime Minister Antonis Samaras is also warning that a win for Syriza could lead to Greece leaving the currency bloc.

Analysts say spillover from the Greek crisis will be more limited this time as the eurozone is in a stronger financial state. But it will add stress and uncertainty as the eurozone struggles.