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“The authors identify 2 major types of statistical data from which semantic representations can be learned. These are denoted as experiential data and
distributional data. Experiential data are derived by way of experience with the physical world and comprise the sensory-motor data obtained through sense receptors. Distributional data, by contrast, describe the statistical distribution of words across spoken and written language. The authors claim that experiential and distributional data represent distinct data types and that each is a nontrivial source of semantic information. Their theoretical proposal is that human semantic representations are derived from an optimal statistical combination CCI-779 mouse of these 2 data types. Using a Bayesian probabilistic model, they demonstrate how word meanings can be learned
by treating experiential and distributional data as a single joint distribution and learning the statistical structure that underlies it. The semantic representations that are learned in this manner are measurably more realistic-as verified by comparison to a set of human-based measures of semantic representation-than those available from either data type individually or from both sources independently. This is not a result of merely using quantitatively more data, but rather it is because experiential and distributional data are qualitatively distinct, yet intercorrelated, types of data. The semantic representations that are learned are based on NVP-AUY922 clinical trial statistical structures that exist both within and between the experiential and distributional data types.”
Objective To estimate the 12-month prevalence of cognitive-enhancing drug use. Design Paper-and-pencil questionnaire HSP990 cell line that used the randomized response technique. Setting University in Mainz, Germany. Participants A total of 2569 university students who completed the questionnaire. Measurements and Main Results An anonymous, specialized questionnaire that used the randomized response technique was distributed to students at the beginning of classes and was collected afterward. From the responses, we calculated the prevalence of students taking drugs only to improve their cognitive performance and not to treat underlying mental disorders such as attention-deficithyperactivity disorder, depression, and sleep disorders. The estimated 12-month prevalence of using cognitive-enhancing drugs was 20%. Prevalence varied by sex (male 23.7%, female 17.0%), field of study (highest in students studying sports-related fields, 25.4%), and semester (first semester 24.3%, beyond first semester 16.7%). To our knowledge, this is the first time that the randomized response technique has been used to survey students about cognitive-enhancing drug use.