"Long Island is continuing to slip, but a modest amount, " says Jonathan Miller, president of Miller Samuel, a New York-based real estate appraisal and consultancy firm.

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Jonathan Miller, an appraiser and president of Miller Samuel Inc.

WSJ: Property Slips in Manhattan

In New York, Jonathan Miller, president and chief executive of appraisal firm Miller Samuel, said an apartment with a view of Manhattan's Central Park can sell for 50% more than one in the same building without the view.

WSJ: What's a View Worth?