(S (S (S (NP (BASENP (NNP Francis) (NNP Everitt)) (PRN (COMMA ,) (NP (BASENP (DT the) (NN experiment) (POS 's)) (BASENP (NNP Principal) (NNP Investigator))) (COMMA ,))) (VP (VP (VBZ stresses) (PP (IN in) (NP (BASENP (DT an) (NN interview)) (PP (IN with) (BASENP (DT the) (NNP New) (NNP York) (NNP Times)))))) (SBAR (SBAR (IN that) (S (BASENP (PRPD their) (NN announcement)) (VP (VBZ is) (ADJP (RB only) (JJ preliminary))))) (CC and) (SBAR (IN that) (S (PRN (COMMA ,) (PP (IN with) (BASENP (JJ further) (NN analysis))) (COMMA ,)) (S (BASENP (PRP they)) (VP (VBP hope) (S (VP (TO to) (VP (VB improve) (NP (BASENP (DT the) (NN precision)) (PP (IN of) (BASENP (PRPD their) (NNS results)))))))))))))) (COLON ;) (S (ADVP (RB currently)) (COMMA ,) (S (BASENP (PRP they)) (VP (VBP say) (SBAR (S (BASENP (PRP they)) (VP (VBP have) (VP (ADVP (RB only)) (VP (VP (VBN detected) (BASENP (DT the) (NN frame) (NN dragging) (NN effect))) (PP (TO to) (PP (IN within) (NP (BASENP (QP (ADJP (JJ plus) (CC or) (JJ minus)) (NN fifteen)) (NN percent)) (PP (IN of) (BASENP (PRPD its) (JJ expected) (NN value))))))))))))))) (PERIOD .))