Fears of a bear market for U.S stock markets came back to the fore Monday with Nobel Prize-winning economist Robert Shiller warning of rock-bottom investor sentiment in his latest research.
The Yale University economist told the Financial Times over the weekend that his confidence surveys were signaling investors were currently at their most fearful of an overvalued market than they have been since the dot-com bubble in 2000.
"It looks to me a bit like a bubble again with essentially a tripling of stock prices since 2009 in just six years and at the same time people losing confidence in the valuation of the market," he told the newspaper in an article published Sunday.
However, analysts and strategists have played down talk of overvalued equity markets, despite seven years of ultra-loose monetary policy.
"Absolutely not ... I just don't see it." Michael Gurka, founder and president of BruinHill Partners, told CNBC on Monday when asked whether he thought U.S. stocks were in a bubble.
"I think that if there is a bubble it's so far down the road that we need to see much higher inflated prices to warrant that."
Instead, there is now "fundamental support" for decent returns in equities during the next couple of years, according to John Stopford, co-head of multi-asset at Investec Asset Management. He told CNBC on Monday that growth in developed markets is above trend and we are in a "drawn-out economic cycle."
"It's taken time for economies to close output gaps, so (the economic cycle) could go on for awhile longer and if that's the case stocks could continue to rally for awhile longer," he said.
It might not be the first time that the Shiller has warned of hefty valuations but his latest comments come just weeks after a significant selloff for global markets that saw major U.S. benchmarks edge into correction territory.
Shiller did add, however, that it remained impossible to time any potential market fall and stressed that it wasn't clear whether U.S. stocks would react badly to a rate hike, with policymakers from the U.S. Federal Reserve meeting later in the week.
"I'm not looking for any big effect," he said. "It's been talked about for so long, everyone knows that it's coming. It's just not much of a big deal."
Richard Kelly, head of global strategy at TD Securities, meanwhile, argued that stocks were in a very different environment compared to previous cycles where the Fed had raised interest rates.
He told CNBC on Monday that the central bank had actively told investors to move into riskier assets like stocks, thus inflating prices for the last seven years.
However, he still wasn't convinced that a stock market bubble had appeared or was about to burst.
"I think it's reasonable to expect that as the Fed starts to hike we may not see the same support within the equity markets that we have in the past because we are going to try to rotate some of that back out of the market," he said.
"That doesn't mean a bubble, but it does mean I think that it's a reasonable bias to at least question whether equities can have the same sort of support as the Fed hikes, than they would (have done) in the past."
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