For the second straight year, a statisticalstudy shows that the Los AngelesLakers' Kareem Abdul-Jabbarhas the highest performance rating inthe National Basketball Association,and Mitch Kupchak leads the WashingtonBullets.

The study, similar to one conductedlast season, is based on an analysisof players' performances through Feb.28 for the Bullets and through Feb.18 for the rest of the NBS.

Players' statistics were put into amathematical formula to determinetheir performance index. Factors fedinto the formula include pointsscored, field-goal and free-throw accuracy,assists, rebounds, steals,blocked shots, turnovers and foulscommitted.

Each of these factors is given aweight, which in some cases variesaccording to whether a player is afront-court or back-court man. Aguard who rebounds well, for instance,wins more points than a forwardor center.

Since a player with more minutesof playing time would generally havemore performance points than someonewith less playing time, the pointsare divided by the number of minutesare divided by the number of minutesplayed to provide a more equal evaluation. Thus, the statistics of a sixthman like Kupchak, who averages 25minutes a game, can be comparedmore fairly to a player who starts andplays 40 minutes per contest.

Abdul-Jabbar, down somewhat fromlast season's 863 performance rating,leads a trio of Phoenix Suns headinginto the final quarter of the season. Alvan Adams ranks a surprising second(.747), while Walter Davis is theleading forward (.733) and teammatePaul Westiphal the top guard (.732).

NBA scoring leader George Gervinof San Antonio (.720) and Chicagocenter Artis Gilmore (.700) are theonly other players at or above.700.

The Bullets are the only team tohave four front-court players -- Kupchak,Bob Dandridge, Wes Unseld andElvin Hayes -- in the top 40. Phoenix,with the recently acquired Truck Robinson(.569), is the only other teamwith more than two.

Most of the veteran Bullets are performingwell above their ratings oflast season, with the most significantimprovements coming from Kupchak,Dandridge, Unseld and Tom Henderson. Dandridge ranks second amongforwards in assists per minute, andUnseld is fourth among centers inthat league in net possessions obtainedfor the second straight year. Kupchak,Dandridge, Kevin Grevey and Hayesall rank in the top 40 in points scoredper minute.