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3 Stocks Rising on Unusual Volume

Tickers in this article: MTRX GHDX AFFY
WINDERMERE, Fla. ( Stockpickr) -- Professional traders running mutual funds and hedge funds don't just look at a stock's price moves; they also track big changes in volume activity. Often when above-average volume moves into an equity, it precedes a large spike in volatility.

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Major moves in volume can signal unusual activity, such as insider buying or selling -- or buying or selling by "superinvestors."

Unusual volume can also be a major signal that hedge funds and momentum traders are piling into a stock ahead of a catalyst. These types of traders like to get in well before a large spike, so it's always a smart move to monitor unusual volume. That said, remember to combine trend and price action with unusual volume. Put them all together to help you decipher the next big trend for any stock.

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With that in mind, let's take a look at several stocks rising on unusual volume today.

Matrix Service (MTRX)

This company provides construction and repair and maintenance services mainly to the energy and energy related industries. This stock is trading up 7.8% at $10.88 in recent trading.

Today's Volume: 271,000

Average Volume: 118,163

Volume % Change: 232%

From a technical perspective, MTRX is surging higher here right off some near-term support at $10.05 and back above its 50-day at $10.79 with above-average volume. This move is quickly pushing MTRX within range of triggering a near-term breakout trade. That trade will hit once MTRX manages to take out some near-term overhead resistance levels at $11.21 to $11.38, and then once it clears $11.67 to $12 with high volume.

Traders should now look for long-biased trades in MTRX as long as it's trending above its 50-day at $10.79, and then once it sustains a move or close above those breakout levels with volume that hits near or above 118,163 shares. If that breakout triggers soon, then MTRX will set up to re-test or possibly take out its next major overhead resistance levels $14.05 to $15.06. The key to testing those levels will be once MTRX takes out $12 with volume, so be watching for that move to trigger soon.

Genomic Health (GHDX)

This company is engaged in the development and commercialization of genomic-based clinical laboratory services that analyze the underlying biology of cancer, allowing physicians and patients to make individualized treatment decisions. This stock is trading up 5.2% at $27.80 in recent trading.

Today's Volume: 468,000

Average Volume: 215,905

Volume % Change: 221%

From a technical perspective, GHDX is bouncing sharply higher here off some near-term support at $25.25 with above-average volume. This bounce is coming after shares of GHDX recently gapped down big from $32 to $25.25 with heavy volume. That gap down has pushed GHDX into modestly oversold territory, since its current relative strength index (RSI) reading is 33.15.