Quantifying Semantic Linguistic Maturity in Children

We propose a method to quantify semantic linguistic maturity (SELMA) based on a high dimensional semantic representation ofwords created from the co-occurrence of words in a large text corpus. The method was applied to oral narratives from 108 children aged 4;0–12;10. By comparing the SELMA measure with maturity ratings made by human raters we found that SELMA predicted the rating of semantic maturity made by human raters over and above the prediction made using a child’s age and number of words produced. We conclude that the semantic content of narratives changes in a predictable pattern with children’s age and argue that SELMA is a measure quantifying semantic linguistic maturity. The study opens up the possibility of using quantitative measures for studying the development of semantic representation in children’s narratives, and emphasizes the importance of word co-occurrences for understanding the development of meaning

Prototype effect and the persuasiveness of generalizations

An argument that makes use of a generalization activates the prototype for the category used in the generalization. We conducted two experiments that investigated how the activation of the prototype affects the persuasiveness of the argument. The results of the experiments suggest that the features of the prototype overshadow and partly overwrite the actual facts of the case. The case is, to some extent, judged as if it had the features of the prototype instead of the features it actually has. This prototype effect increases the persuasiveness of the argument in situations where the audience finds the judgment more warranted for the prototype than for the actual case (positive prototype effect), but decreases persuasiveness in situations where the audience finds the judgment less warranted for the prototype than for the actual case (negative prototype effect)

ChildFreq: An Online Tool to Explore Word Frequencies in Child Language

This technical report describes the implementation and use of ChildFreq, a tool for assessing lexical norms of children from one to seven years old. As the name implies, ChildFreq works by extracting word frequencies from a large corpus of child language. These can then be ordered by age or mean length of utterance, and it is also possible to split the data by the children’s gender. A query of words to count the frequency of produces both a line chart and a table with more detailed information. The child language data is taken from the English part of the CHILDES database 1 and comprises more than 5,000 transcriptions,a total of ≈ 3, 500, 000 word tokens. The children’s ages range from six months to seven years, with most children being three years old. ChildFreq is freely available online a

An Investigation into the Perception and Production of Slow Rhythms

Appreciation and production of musical rhythm is a human universal and, as with other human capacities, it is imperative to understand the extent of our capacity to perceive and produce rhythm. This thesis presents my work on the cognitive and perceptual aspects of rhythm perception and production at a slow tempi. In Paper I I establish that rhythm production, such as keeping the beat to a metronome sequence, gets subjectively more difficult at slower tempi. Difficulty increases gradually with slower tempo, however, there was a was marked increase in rated difficulty when there was more than 1800 ms between each metronome sound, supporting Repp’s (2006) notion of at what tempo keeping a rhythm becomes difficult. Paper II developed a computational cognitive model of rhythm categorization. The model used the resonance theory framework by Large (2010) to model behavioral data on how musicians categorize musical rhythm. The categorization made by the computational model and the categorizations made by the musicians agreed well, supporting the notion that resonance theory is a viable model of rhythm perception. Paper III replicated the study by Bolton (1894) on the auditory illusion subjective rhythmization. Paper IV further explored aspects of this illusion and tested two theoretical explanations of why this illusion occurs. The results strongly favored the resonance theory explanation of subjective rhythmization. In connection to rhythm perception at slow tempi, the paper developed an argument for how participants' experience of subjective rhythmization relates to their slower limit of rhythm perception. In Paper V I show that conventional methods for measuring timing performance do not work correctly when applied to data from rhythmic timing task performed at tempi slower than 30 BPM. A solution to this problem is presented in the form of a problem specific Bayesian model, which was subsequently used to calculate timing variability in Papers VI and VII. Paper VI examine the relationship between auditory working memory, sensorimotor synchronization performance, and memory capacity for rhythms. The results showed that auditory working memory and memory capacity for rhythms are related. However, the influence of memory capacity on synchronization performance showed no interaction with sequence tempo, suggesting that auditory memory does not play an integral role in rhythm perception. Paper VII showed that, when the tempo is sufficiently slow, performing rhythmic timing demands attentional resources and involvement of executive control. This result resonates with neural models of timing that suggest a dedicated timing mechanism for short intervals and a general, cognitive timing mechanism for longer intervals

The State of Naming Conventions in R

Most programming language communities have naming conventions that are generally agreed upon, that is, a set of rules that governs how functions and variables are named. This is not the case with R, and a review of unofficial style guides and naming convention usage on CRAN shows that a number of different naming conventions are currently in use. Some naming conventions are, however, more popular than others and as a newcomer to the R community or as a developer of a new package this could be useful to consider when choosing what naming convention to adopt