Reading is a fundamental skill for functioning in today’s society. Given the breadth of activities that require reading, it is important to develop a comprehensive model of basic reading processes. Furthermore, considering that many pictures co-appear with words in everyday life, it is imperative to understand the nature of picture identification processes, as well as how they interact with reading processes. As such, the present thesis focuses on developing a model of reading and extending it to include picture processing. In the present research, experiments on word identification (Experiments 1 and 2) examined onset reaction time (RT) in a word naming task using an additive factors method. The pattern of additive and overadditive joint effects on naming RT among Instructions (INST: name all, name words), Word Frequency (WF: log10HAL), Semantic Neighbourhood Density (SND: Inverse Ncount), and Word Type (WT: regular, exception) supported a cognitive chronometric architecture consisting of at least two cascaded stages of processing, with the orthographic lexical system as the locus of the INST x WF and the INST x SND interactions, and the phonological output system as the locus of the WF x WT and the SND x WT interactions. Additivity between INST and WT supports the notion that these variables affect separable systems, and a WF x SND interaction supports a common locus of their effects. These results support a dual-route cascaded model over parallel processing models of basic reading. We also examined response duration (RD) in these data by recording and hand-marking vocal responses, which provides evidence that reading processes are ongoing even after the initiation of a vocal response, and supports the notion that the more lexically a word is read, the shorter the RD. As such, the effects of WT and INST on RD were opposite to their effects on RT. Given the dissociating effects between RT and RD, these results provide new challenges to all models of basic reading processes. Experiments on picture and word identification (Experiments 3 and 4) involved localizing common systems and connections between these processes, and served to extend the dual-route model of reading. These experiments examined naming RT and RD for exception and regular words, and their corresponding pictures. The pattern of joint effects on RT among Format (pictures, words), Picture-Orthography Agreement, WF, and WT (regular, exception) supported a triple-route cascaded model. The results suggest the orthographic lexical system is accessed for both picture and word naming, and demonstrated a dissociation between regular and exception words on RT versus RD, whereas pictures consistently yielded an exception item advantage for both measures. Experiment 4 examined Arabic digits and their corresponding number words, and found that Arabic digits produce shorter RDs than number words. In general, the results suggest that the picture and word identification systems are strongly coupled between the picture memory system and the orthographic lexical system, particularly for items that rely on “whole-word” lexical representations. We argue that RD provides a wider window for exploring cognition, and a converging measure of lexical processing, which must be considered when studying basic identification processes of any stimulus type. The development of a comprehensive model of basic reading processes will help identify behavioural markers of normal reading processes, and will serve to advance research on basic word recognition. In addition, given that a broad definition of ‘literacy’ should include picture processing, the development of a model that includes picture processing will serve to advance research on how reading and picture processing interact with each other, which may be critical for individuals with low literacy skills.

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Made available in DSpace on 2016-04-29T13:18:02Z (GMT). No. of bitstreams: 1 pre-versao eletronica.pdf: 1665329 bytes, checksum: fb0986a0146d93d0706058a1172c3b0c (MD5) Previous issue date: 2005-04-29 / The purpose of this research was to analyze the production of observing responses (OR) emitted by humans when the consequences were the production of stimuli related to a VI or EXT schedule. Six participants between 22 and 42 years old were distributed in 2 groups. Participants in Group 1 were first exposed to a multiple schedule VI 20s-EXT with components of 90 seconds in average. During the VI component, presses on a button produced points exchanged for money at the end of each session. After achieving 0.9 or more in a discrimination index (responses during VI divided by responses during VI plus responses during EXT) for 3 or more consecutive sessions, these participants were exposed to a mixed schedule VI 20s-EXT, with the possibility of emiting responses (OR) on a second button that changed the schedule from mixed to its multiple equivalent for the time the button remained pressed. Group 2 participants were exposed directly to this second condition. Participants of Group 2 achived discrimination indexes higher than 0,9 and Group 1 participants did not achived the criterion. The absence of dircrimination of the responses of Group 1 participants was discussed in terms of relevance of the stimuli produced by the OR and in terms of accidental chaining. All participants exposed to the mix VI EXT with OR produced OR. Two participants emitted OR in a situation where they represented effort economy. All participants produced the stimulus related to EXT in geater or equal frequency and duration than the stimulus related to VI / O objetivo desta pesquisa foi analisar situações relacionadas à produção de respostas de observação (RO) emitidas por humanos quando as conseqüências eram a produção de estímulos relacionados a um esquema VI ou a EXT. Seis participantes, com idades entre 22 e 42 anos, foram distribuídos em dois grupos. Os participantes do Grupo 1 foram primeiro expostos a um esquema múltiplo VI 20s-EXT com componentes de 90 segundos em média. Durante os componentes VI, pressões em um botão produziam pontos que eram trocados por dinheiro ao final da sessão. Após atingir um índice de discriminação de 0,9 ou mais (respostas durante VI dividido pela soma das respostas durante VI com as respostas durante EXT) por três ou mais sessões consecutivas, os participantes seriam expostos a um esquema misto VI 20s-EXT, com possibilidade de emissão de respostas (RO) em um segundo botão que mudavam o esquema de misto para seu equivalente em múltiplo pelo tempo que o botão permanecesse pressionado. Os participantes do Grupo 2 foram expostos diretamente a esta segunda condição. Os participantes do Grupo 2 atingiram índices de discriminação maiores que 0,9 e os participantes do Grupo 1 não atingiram este critério. A ausência de discriminação nas respostas dos participantes do Grupo 1 foi discutida em termos da relevância dos estímulos produzidos pela RO e em termos da possibilidade de encadeamento acidental. Todos os participantes expostos ao mix VI EXT com resposta de observação produziram respostas de observação. Dois participantes do Grupo 2 emitiram RO numa situação em que estas representavam economia de esforço. Estímulos relacionados com EXT foram produzidos com maior ou igual freqüência e duração que os estímulos relacionados com VI

Transportation agencies are introducing new strategies and techniques that will improve traffic incident management. Apart from other indicators, agencies measure the performance of the strategies by evaluating the incidents timeline. An effective strategy has to reduce the length of the incident timeline. An incident timeline comprises various stages in the incident management procedure, starting when the incident was detected, and ending when there is the recovery of normal traffic conditions. This thesis addresses three issues that are related to the traffic incident timeline and the incident management strategies. First, co-location of responding agencies has not been investigated as other incident management measures. Co-location of incident responders affects the incident timeline, but there is a scarcity of literature on the magnitude of the effects. Evaluation of the co-location strategy is reflected by the response and verification durations because its effectiveness relies on improving communication between agencies. Investigation of the response and verification duration of incidents, before and after operations of a co-located Traffic Management Center (TMC) is done by using hazard-based models. Results indicate that the incident type, percentage of the lane closure, number of responders, incident severity, detection methods, and day-of-the-week influence the verification duration for both the before- and after- period. Similarly, incident type, lane closure, number of responders, incident severity, time-of-the-day, and detection method influence the response duration for both study periods. The before and after comparison shows significant improvements in the response duration due to co-location of incident response agencies. Second, the incident clearance duration may not necessarily reflect how different types of incidents and various factors affect traffic conditions. The duration at which the incident influences traffic conditions could vary – shorter than the incident duration for some incidents and longer for others. This study introduces a performance measure called incident impact duration and demonstrates a method that was used for estimating it. Also, this study investigated the effects of using incident impact duration compared to the traditionally incident clearance duration in incident modeling. Using hazard-based models, the study analyzed factors that affect the estimated incident impact duration and the incident clearance duration. Results indicate that incident detection methods, the number of responders, Traffic Management Center (TMC) operations, traffic conditions, towing and emergency services influence the duration of an incident. Third, elements of the incident timeline before the clearance duration have been overlooked as factors that influence the clearance duration. Incident elements before the clearance duration include verification time, dispatch duration, and the travel time of responders to the incident scene. This study investigated the influence of incident timeline elements before clearance on the extent of the clearance duration. Also, this study analyzed the impact of other spatial and temporal attributes on the clearance duration. The analysis used a Cox regression model that is estimated using the Least Absolute Shrinkage and Selection Operator (LASSO) penalization method. LASSO enables variable selection from incidents data with a high number of covariates by automatically and simultaneously selecting variables and estimating the coefficients. Results suggest that verification duration, response travel duration, the percentage of lane closure, incident type, the severity of an incident, detection method, and crash location influence the clearance duration.