The nationwide housing market is improving, alongside an uptick in the economy and lower mortgage and unemployment rates, but sellers in New Jersey are holding their homes off the market.

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If you're interested in selling your house, now would seem to be the perfect time. So what's going on in the Garden State?

"Many prospective sellers are not listing their homes because they're afraid they won't get the true value of the house," said Pat O'Keefe, director of economic research at CohnReznick. "New Jersey continues to have a large inventory of foreclosed properties that haven't yet come to market, therefore those owners who would list their homes are unwilling to put their homes on the market because they'd be competing with those distressed properties."

O'Keefe said home prices in New Jersey are up about four percent this year compared to 2012, but that is not as drastic of an increase as other parts of the country have seen.

Another problem is the large number of appraisals done since the Great Recession, which revealed that New Jersey homes aren't worth what they once were.

So even if a buyer is willing to spend more on a home that they want, it will be more difficult for them to get a mortgage because the official value of the home may not match the price.

"It's a conundrum that is not easily resolved," said O'Keefe. "Until we work down the state's enormous inventory of foreclosure properties, it is unlikely that we will see much progress before the end of 2014."