ok, read your link. Median house price is the point where half of the houses sold durring that time period sold for more, and half sold for less. If you get a structural shift in the type of houses being sold, then the median can swing wildly without any real change in the price of each house. Infact, the median can increase as prices are falling.
The stastical weakness in the median happened in late 06 to early 07, when subprime financing fell apart. Lower priced houses suddenly stopped being financed as often, so sales fell apart in the lower costs areas. Then, since fewer low cost houses were being sold, the median moved up even though the actual selling value of any house changed very little.
This may also be happening now, just slightly differently. Before only the cheapest of houses were selling. Now if people, feeling more comfortable with the economy, buy more expensive houses (in total number of houses sold) the median price can go up even though no change in actual sales values of each house was recorded.
Also, one or two month small moves in the median price are often trumpeted in the media as “turning points” or “signs of stabilzation” when really they are usually just stastical anomilies that could easily reverse themselves the next month. If we get 5-6 months of constantly increasing median prices, then we can ask if prices are actually increasing.