Chess masters and beginners were shown chess pieces on a chessboard, and then asked to reconstruct the locations of the chess pieces from memory. Some of the pieces were shown from normal games $($normal arrays$)$ and others were random arrays. Researchers found that:

Chess masters had superior memory relative to chess beginners for chess pieces in normal arrays, and the two groups had equal memory for chess pieces in random arrays.

Chess masters had superior memory relative to chess beginners for chess pieces in both normal and random arrays.

Chess masters had superior memory relative to chess beginners for chess pieces in random arrays, and the two groups had equal memory for chess pieces in normal arrays.

Chess masters had superior memory relative to chess beginners for chess pieces in normal arrays, and the inferior memory for chess pieces in random arrays.