University of Memphis

About: University of Memphis is a education organization based out in Memphis, Tennessee, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 7710 authors who have published 20082 publications receiving 611618 citations. The organization is also known as: U of M.

vocd: A theoretical and empirical evaluation

Abstract: A reliable index of lexical diversity (LD) has remained stubbornly elusive for over 60 years. Meanwhile, researchers in fields as varied as stylistics, neuropathology, language acquisition, and even forensics continue to use flawed LD indices — often ignorant that their results are questionable and in some cases potentially dangerous. Recently, an LD measurement instrument known as vocd has become the virtual tool of the LD trade. In this paper, we report both theoretical and empirical evidence that calls into question the rationale for vocd and also indicates that its reliability is not optimal. Although our evidence shows that vocd's output (D) is a relatively robust indicator of the aggregate probabilities of word occurrences in a text, we show that these probabilities — and thus also D — are affected by text length. Malvern, Richards, Chipere and Duran (2004) acknowledge that D (as calculated by vocd's default method) can be affected by text length, but claim that the effects are not significant for t...

Who underreports dietary intake in a dietary recall? Evidence from the Second National Health and Nutrition Examination Survey.

Abstract: The present study sought to identify the presence and degree of apparent underreporting of dietary intake in 11,663 participants in the Second National Health and Nutrition Examination Survey (NHANES II). Self-reported dietary intake was compared with estimated basal metabolic rate. Underreporting was based on cutoff limits that identified plausible levels of energy expenditure for adult individuals. Results indicated that up to 31% of adults in this sample may have underreported dietary intake. Those individuals at greatest risk of underreporting were less well educated and heavier. The Sex x Race interaction indicated that for both ethnic categories, women were more likely to underreport than men, but the difference between men and women was greater among Caucasian participants. It is concluded that such factors as reduced energy needs, deliberate falsification, and measurement error inherent in dietary assessment contribute to apparent underreporting, and this occurs in a large percentage of dietary data.

Population lateralisation and social behaviour: a study with 16 species of fish.

Abstract: We investigated turning responses in 16 species of fish faced with a vertical-bar barrier through which a learned dummy predator was visible. Ten of these species showed a consistent lateral bias to turn preferentially to the right or to the left. Species belonging to the same family showed similar directions of lateral biases. We performed an independent test of shoaling tendency and found that all gregarious species showed population lateralisation, whereas only 40% of the nongregarious species did so. The results provide some support to the Rogers (1989) hypothesis that population lateralisation might have been developed in relation to the need to maintain coordination among individuals in behaviours associated with social life.

The size ramsey number

Abstract: Let denote the class of all graphsG which satisfyG→(G 1,G 2). As a way of measuring minimality for members of , we define thesize Ramsey number ř(G 1,G 2) by . We then investigate various questions concerned with the asymptotic behaviour ofř.