( ( Correlation ( among observations ) ) ( often ( ( ( arises ( from ( multiple measurements ) ) ) ( on ( ( the ( same subject ) ) ( such ( as ( in ( ( ( ( ( ( longitudinal studies ) , ) ( repeated ( measures designs ) ) ) , ) or ) ( ophthalmology studies ) ) ) ) ) ) ) ) . ) ) )
(ROOT (S (NP (NP (NNP Correlation)) (PP (IN among) (NP (NNS observations)))) (ADVP (RB often)) (VP (VBZ arises) (PP (IN from) (NP (JJ multiple) (NNS measurements))) (PP (IN on) (NP (NP (DT the) (JJ same) (NN subject)) (PP (JJ such) (IN as) (PP (IN in) (NP (NP (JJ longitudinal) (NNS studies)) (, ,) (NP (JJ repeated) (NNS measures) (NNS designs)) (, ,) (CC or) (NP (JJ ophthalmology) (NNS studies)))))))) (. .)))
Correlation among observations often arises from multiple measurements on the same subject such as in longitudinal studies, repeated measures designs, or ophthalmology studies.
(ROOT (S (NP (JJ Multiple) (NN fission)) (VP (VBZ is) (ADVP (RBR more) (RB often)) (VP (VBN observed) (PP (IN among) (NP (NNS protists))))) (. .)))