US Should Reevaluate Its Position on Bosnia It is time for the United States to either reevaluate its policy in Bosnia or admit we have been lying. It is extremely hypocritical to contend we are opposed to ''ethnic cleansing'' while we facilitate it by supplying the NATO air power to change the balance of power in the war. More than 100,000 Bosnian Serbs have been expelled from their homes. These Bosnian Serbs are now refugees that are no less ''cleansed'' than those other Bosnians for whom we have previously professed such concern. If destruction of the Bosnian Serbs is not the objective of US foreign policy, then we should immediately begin massive NATO bombing of the Croatian and Bosnian Muslim military forces that are mounting the current offensive in Bosnia. We must either come now to the rescue of the Serbs who lived for more than 400 years on the same land in Bosnia from which they are now being ''cleansed'' or admit that we are not and never were neutrals in this war. W. Dan and Sonja D. Myers Houston Ability vs. performance When the author of the opinion-page article ''The Myth of Biased Exams,'' Sept. 15, claims that ''tests don't create discrepancies of ability and performance; they merely measure them,'' he is wrong. While tests (sort of) ''measure'' performance, they do not measure ability. ''Ability'' is only a hypothetical entity, inferred from performance samples. The main argument against affirmative action that the author and others present is that affirmative action treats persons as members of racial and gender groups, while ignoring their individual merit. Yet, ironically, on closer inspection, this so-called individual merit derives from membership in another group: those who received a particular test score. The best statistical prediction for an aggregate always contains a good deal of error in predicting the actual performances of the individuals in the group. Altogether, then, selection procedures based on such statistical formulae and ignoring individual variance may well be ''efficient'' and profitable for an employer. But to justify the use of probabilistic selection by the practical benefits for the organization is one thing. To claim moral superiority for judgments allegedly based on individual merit, when a closer look shows that they in fact ignore the individual, is something else. It sounds like Orwellian newspeak to me. Franz Samelson Manhattan, Kan. Include all branches of Abrahamic faith In the opinion-page article ''Theology's Place in Mideast Peace,'' Aug. 22, the author states that ''a lasting peace [in the Middle East] must take Islamic doctrine into account.'' I would like to go one step further and suggest that lasting peace in the Middle East should take all the branches of the Abrahamic faith into account. For one thing, the reality of modern Israel is rooted in Biblical promise of the Holy Land, a promise that Jewish settlers in the West Bank still call upon to justify their opposition to the extension of Palestinian self-rule. The new settler movement ''Zu Eretznu'' (This is Our Land) is relying on recent Rabbinic rulings to argue that it is morally wrong for the government of Israel to order army soldiers to remove settlers from their improvised encampments. The author's call on Muslim clerics to clarify Islam's position toward Israel should be balanced by a call on Jewish rabbis to clarify Judaism's position toward territorial compromises in the Holy Land, the Golan Heights, and South Lebanon. And the final status of Jerusalem cannot be determined without considering the views and claims of various Christian denominations. Abe Elfadel Brookline, Mass.