Graph Interpretation Research Articles

Learning Impact of a Virtual Brain Electrical Activity Simulator Among Neurophysiology Students: Mixed-Methods Intervention Study.

BackgroundVirtual simulation is the re-creation of reality depicted on a computer screen. It offers the possibility to exercise motor and psychomotor skills. In biomedical and medical education, there is an attempt to find new ways to support students’ learning in neurophysiology. Traditionally, recording electroencephalography (EEG) has been learned through practical hands-on exercises. To date, virtual simulations of EEG measurements have not been used.ObjectiveThis study aimed to examine the development of students’ theoretical knowledge and practical skills in the EEG measurement when using a virtual EEG simulator in biomedical laboratory science in the context of a neurophysiology course.MethodsA computer-based EEG simulator was created. The simulator allowed virtual electrode placement and EEG graph interpretation. The usefulness of the simulator for learning EEG measurement was tested with 35 participants randomly divided into three equal groups. Group 1 (experimental group 1) used the simulator with fuzzy feedback, group 2 (experimental group 2) used the simulator with exact feedback, and group 3 (control group) did not use a simulator. The study comprised pre- and posttests on theoretical knowledge and practical hands-on evaluation of EEG electrode placement.ResultsThe Wilcoxon signed-rank test indicated that the two groups that utilized a computer-based electrode placement simulator showed significant improvement in both theoretical knowledge (Z=1.79, P=.074) and observed practical skills compared with the group that studied without a simulator.ConclusionsLearning electrode placement using a simulator enhances students’ ability to place electrodes and, in combination with practical hands-on training, increases their understanding of EEG measurement.

The State of the Art in Empirical User Evaluation of Graph Visualizations

While graph drawing focuses more on the aesthetic representation of node-link diagrams, graph visualization takes into account other visual metaphors making them useful for graph exploration tasks in information visualization and visual analytics. Although there are aesthetic graph drawing criteria that describe how a graph should be presented to make it faster and more reliably explorable, many controlled and uncontrolled empirical user studies flourished over the past years. The goal of them is to uncover how well the human user performs graph-specific tasks, in many cases compared to previously designed graph visualizations. Due to the fact that many parameters in a graph dataset as well as the visual representation of them might be varied and many user studies have been conducted in this space, a state-of-the-art survey is needed to understand evaluation results and findings to inform the future design, research, and application of graph visualizations. In this article, we classify the present literature on the topmost level into graph interpretation, graph memorability, and graph creation where the users with their tasks stand in focus of the evaluation, not the computational aspects. As another outcome of this work, we identify the white spots in this field and sketch ideas for future research directions.

On Some Multinomial Sums Related to the Fibonacci Type Numbers

Abstract In this paper we investigate Fibonacci type sequences defined by kth order linear recurrence. Based on their companion matrix and its graph interpretation we determine multinomial and binomial formulas for these sequences. Moreover we present a graphical rule for calculating the words of these sequences from the Pascal’s triangle.

Diagnosis of the reading and interpretation of statistical graphs by undergraduate students from economic-administrative sciences programs at the University of Guadalajara

Recently, statistical reasoning has been of vital importance not only in quantitative analysis but also in the interpretation of graphs at all educational levels. There are students that can make calculations almost immediately but are not able to interpret or present their ideas graphically. In this way, the present study seeks to conduct a diagnostic of the problems that economic-administrative students have when reading and interpreting graphs in their statistics courses. For this, a Spanish version of the test Comprehensive Assessment of Outcomes in Statistics (CAOS) was administered. This instrument allows for the determination of reasoning applied to different types of statistical graphs and in some cases to determine what type of calculation is required to do it. The instrument was applied to 138 undergraduate students from the economic-administrative area of the University of Guadalajara during January-June 2018. The results show that a large percentage of students confuse a normal distribution with a uniform one and that they are unable to distinguish that a bias can be determined from the measures of central tendency and dispersion, as well as other statistical reasoning difficulties. This may be as a result of a deficiency that exists in statistical teaching, an insufficient mathematical preparation on the part of the students, among other factors.

When IPCC graphs can foster or bias understanding: evidence among decision-makers from governmental and non-governmental institutions

To develop effective climate change policy, decision-makers need to have the best possible understanding of the available climate science. The IPCC Assessment Reports therefore aim to lay the foundation for informed political decision-making by providing policy-relevant information. But how successful are IPCC reports at communicating key findings? Although IPCC reports display key information in graphs, the interpretation of such graphs has received little attention. Here we provide an empirical evaluation of IPCC graph comprehension among IPCC target audience (N = 110), (political) decision-makers from climate-related (non-)governmental organizations from 54 countries, and a comparative sample of German junior diplomats, representing future international decision-makers (N = 33). We assess comprehension of current climate change risk visualizations using two IPCC graphs, one that employs principles of intuitive design, and one that violates principles of intuitive design. Results showed that (i) while a minority of IPCC target audience misinterpreted the intuitive graph, (ii) the majority of participants systematically misinterpreted the counter-intuitive graph, drawing the opposite conclusion from what was meant to be conveyed by the graph, despite (iii) having high confidence in the accuracy of their interpretation. Since misinterpretation of IPCC graphs does not allow for optimal use of the scientific information for policy-making, the results emphasize the importance of IPCC graphs that follow the principles of intuitive design.

Reading Tutors’ Interpretation of Curriculum-Based Measurement Graphs

This study examined reading tutors’ interpretation of reading progress-monitoring graphs. A think-aloud procedure was used to evaluate tutors at two points in time, before and after a year of service as an AmeriCorps reading tutor. During their service, the reading tutors received extensive training and ongoing coaching. Descriptive results showed a positive change from the Time 1–think-aloud (pretest) to the Time 2–think aloud (posttest). There were statistically significant changes from Time 1 to Time 2 for the majority of graph interpretation variables measured. Data suggest that the right type of support and training may serve to enable reading tutors to develop the skills to contribute to data-based decision-making within multitiered systems.

외국의 중등 교육과정 분석을 통한 통계 영역 교육과정 개선 방안 탐색

This study tried to improve Korean statistics curriculum by exploring what aspects statistics are viewed in foreign statistics curriculum, what is given on achievement standards or learning content, and what points should be paid attention to. Statistical curricula were analyzed in 10 countries, including New Zealand, California USA, Singapore, England, Japan, China, British Columbia Canada, Finland, Australia and International Baccalaureate. The results of this study propose to deal with pattern and relationship discovery, data-based argumentation, and exploration of variability for literacy to deal with big data in the field of statistics according to the document system of the 2015 revised mathematics curriculum. It is suggested to introduce dot plots, box plots, and interquartile ranges in the contents of statistics education, and further elaborate Guidelines for Teaching and Learning in the expression and interpretation of graphs, representative values and scatter plots, correlations, data collection and samples, and statistical estimation. Finally, we proposed that curriculum should be designed to ensure that the content of statistical education continues to deepen.

The Efficacy of GeoGebra-Assisted Instruction on Students’ Drawing and Interpretations of Linear Functions

The purpose of this study was to explore the effectiveness of GeoGebra assisted instruction on students’ achievement in drawing graphs of linear functions and interpretation of the representations of linear functions. These aspects of linear functions tend to pose a challenge to many students. The non-equivalent control group pre-test-post-test quasi-experimental research design was used in the study. The sample was 94 Grade 9 students from three secondary schools in a province in South Africa. Two schools formed the control groups and one school was the experimental group. Data were collected using achievement tests. The tests results were analysed using inferential statistics (Kruskal-Wallis and Mann-Whitney U comparison tests) at 0.05 level of significance. Statistically significant differences were found between the groups with respect to drawing and interpretation of linear functions graphs with the experimental group obtaining the highest mean scores. The findings suggest that GeoGebra assisted instruction might be a way of enhancing students’ ability to draw the graphs of linear functions and analyse and interpret the representations of linear functions.

Middle School Students’ Graph Skills and Affective States about Graphs

This survey design study was designed to test whether the graph skills and affective states of middle school students about graphs differ by their gender, grade level, and graph types (line, bar, and pie). The data collection instruments consisted of two scales developed by the authors and a Graph Skills Test, which consisted of graph questions from the previous TIMSS and PISA exams. Based on the findings, while middle school students were found to succeed at reading the data level graph questions, they were found to struggle in questions requiring higher graph skills, such as graph interpretation and graph construction. As for the affective states investigated, participants were found to hold high self-efficacy beliefs and positive attitudes toward graphs. No significant difference among the dependent variables (graph skills, self-efficacy beliefs about graphs, attitudes toward graphs, and graph literacy perceptions) was found by gender; however, grade level and graph type variables were found to impact students’ graph skills, graph attitudes, and personal graph literacy perceptions. Middle school students with less school experience with graphs (seventh graders) were found to hold more positive attitudes toward graphs than the eighth graders. On the contrary, eighth graders were found to perform better at graph questions requiring interpretations of the graph data. Also, participants in all subgroups were found to hold significantly higher personal graph literacy perceptions for the bar graphs, than the line graphs and pie charts. Based on the findings of the study, while middle school students were found to hold positive affective states about graphs, they were found to lack advanced graph skills. In agreement with the previous literature, it is recommended that graph literacy should become a dedicated part of the school curriculum.

Distance Fibonacci Polynomials

In this paper, we introduce a new kind of generalized Fibonacci polynomials in the distance sense. We give a direct formula, a generating function and matrix generators for these polynomials. Moreover, we present a graph interpretation of these polynomials, their connections with Pascal’s triangle and we prove some identities for them.

On a hypergraph probabilistic graphical model

We propose a directed acyclic hypergraph framework for a probabilistic graphical model that we call Bayesian hypergraphs. The space of directed acyclic hypergraphs is much larger than the space of chain graphs. Hence Bayesian hypergraphs can model much finer factorizations than Bayesian networks or LWF chain graphs and provide simpler and more computationally efficient procedures for factorizations and interventions. Bayesian hypergraphs also allow a modeler to represent causal patterns of interaction such as Noisy-OR graphically (without additional annotations). We introduce global, local and pairwise Markov properties of Bayesian hypergraphs and prove under which conditions they are equivalent. We also extend the causal interpretation of LWF chain graphs to Bayesian hypergraphs and provide corresponding formulas and a graphical criterion for intervention.

UMA PROPOSTA DE SEQUÊNCIA DIDÁTICA PARA ENSINO DE GRÁFICOS ESTATÍSTICOS A PARTIR DA INTERSECCIONALIDADE ENTRE SEXO E RAÇA COM TEMÁTICAS DE UMA ANÁLISE SOCIOECONÔMICA

Este artigo tem por objetivo analisar uma atividade construída com o foco na interpretação de gráficos estatísticos a partir de temáticas que versem sobre a interseccionalidade de sexo e raça, considerando aspectos econômicos e sociais das cidades de Salvador-BA e São Paulo-SP, entre 2011 e 2017. A importância deste tema consiste em apresentar discussões referente à desigualdade racial, sobretudo das mulheres negras, no mercado de trabalho. A visibilidade desse tema é relevante considerando a persistência do racismo estrutural em diferentes setores econômicos, bem como na ausência de equidade social para a população negra. Utilizamos como metodologia de pesquisa qualitativa, para analisar de forma crítica e reflexiva os dados estatísticos apresentados através de órgãos e instituições de pesquisa nacional. Os dados serviram para a construção de atividades destinadas aos(às) alunos(as) de Ensino Médio da Educação Básica para discutir, a partir de análises de gráficos, o lócus ocupado pela mulher negra na sociedade brasileira, tomando como amostra as cidades já citadas, além das regiões do país em que se situam. Portanto, trazê-las para esta discussão torna-se relevante, já que o problema do racismo estrutural ainda é visível na sociedade, particularmente no mercado de trabalho, foco deste estudo. Assim, discutir essa temática é necessária para que estudantes possam analisar e compreender a partir de um olhar crítico e reflexivo o lugar da mulher negra na sociedade, a partir da interpretação de gráficos estatísticos de dados sobre educação e renda, focado no letramento estatístico.

Teaching kinematics with OZOBOT: a proposal to help improve student’s graph interpretation skills

In this paper, we aim to show strategies for improving graph interpretation skills at middle and high school students using OZOBOT® BIT, a small and relatively low-cost programmable robot which had been used to teach programming to young children. OZOBOT’s speed can be controlled by drawing lines with colour codes, as well as through a visual block programming system. We show how to take advantage of these features of the robot by recording appropriate motions that students can explore by video analysis, manipulating data, characterizing the motion and associating graphs to predictions of physical models.

Efficient operation of oil producing wells in non-stationary fluid withdrawal mode

The article deals with the efficient non-stationary well operating mode during fluid withdrawal. In this well operating mode, the optimal pump switching periods are identified to increase the oil flow rate and reduce the water content of the fluid. The purpose of the study is to improve the efficiency of pilot production wells operation. A descriptive method was used during the study, which involved analysis of the reservoir-well-pump system transient phenomena on a simulation stand, interpretation of transient graphs, comparison and synthesis of the results. The paper presents the results of experimental studies of transient pressure changes on the simulation stand for different pump operating modes. The results of the research have shown that the pressure change depends on the pump operating mode, i.e. reservoir characteristics depend on the change in the hydraulic resistance of the reservoir-well-pump system.

Point Estimation with Markers for Effective Mobile Auditory Graphs

While researchers have performed numerous studies to understand the human interpretation of visual graphs in reading, comprehending and interpreting displayed data; visually impaired (VI) students still face many challenges that prevent them from fully benefiting from these graphs in class. In this study, we conducted a test with 20 students to track the work described in studies in an expanded scenario. As we have tried to answer the question as to whether adding multi-reference mapping of sonification to auditory graphs could improve the of point estimation accuracy in non-visual condition. We also emphasize the efficiency of the performance of multi-reference graphs to make them as efficient as mapping using single pitch. Our proposed study improved performance of multi-reference task completion time by having fewer reference note. The results help provide empirical evidence that the multi-reference mode provides more accurate results than the single-pitch mode and confirms that adding contexts to auditory graphs could be used for better comprehension.

Implementation of DSK TMS320C6416T Module in Modified Stethoscope for Lung Sound Detection

This paper presents a design of digital stethoscope that is modified using DSK TMS320C6416T. This modified stethoscope is proposed for helping the doctor to make a true decision and the same perception on the symptoms of someone’s disease. Using the conventional stethoscope usually gives drawback, such as the doctors usually makes misinterpretation on the auscultation. The reason is because of the errors that occur due to the difference on the sensitivity of the ear and the experiences of the doctor. This research offers a DSK TMS 320C6416T as an instrumentation system for identification and analysis on the lung sound. The modified design of the digital stethoscope that is proposed in this research gives benefit to the users because it provides the result in the form of the signals that can be monitored in the PC. The results of this designed stethoscope showed the interpretation of graphs in the form of the spectrogram and scalogram which will help the simplification on the analysis of lung sounds as well as to minimize or avoid the limitations of hearing problems in the process of auscultation. The method used in lung sound analysis in this research includes Fourier Transformation that is then developed into a Short-Time Fourier transform (STFT) and continued to the Wavelet Transform. Based on the test data for normal lung sounds, it was found that the working frequency range was 90 to 1265 Hz. The adventitious sounds were found with frequency range from 60 to 1980 Hz. In this research, it was also found that the lung sounds were at the frequency range from 90 to 1015 Hz for direct measurement to patients.

Systematic Errors in Video Analysis

Video analysis helps students to connect physical, mathematical, and graphical models with the phenomena that the models represent and improves student kinematic graph interpretation skills. The wide-spread availability of easy to use software packages like Logger Pro (Vernier), Capstone (PASCO), and Tracker have led to many introductory physics courses adopting video analysis techniques in the classroom. Such uses include high-speed cameras to study rocket launches and other innovative applications. In this paper, we will look at ways in which some common systematic errors can affect outcomes.

The Relation between Effective Temperature and Thermal Sensation Vote in Tropical Vernacular Houses

One of the factors to enable energy efficiency in buildings is creating thermal comfort for the occupants of buildings so that the artificial vaporization is not required. The thermal sensation vote (TSV) is an indicator in analyzing the occupants’ satisfaction on the thermal comfort of their buildings. Some climate variables that relate to the TSV include air temperature, humidity, and wind speed. The three variables can be combined into a variable using a psychrometric chart. The combined variable is known as an effective temperature. The present research aims at analyzing the connection between effective temperature and TSV in vernacular houses in the tropical mountain and beach locations and comparing the results of the analysis. The quantitative method was employed in the research by measuring the variables of climate using a thermal measuring instrument. The TSV was measured with ASHRAE (American Standard of Heating, Refrigerating, Air-Conditioning Engineer)’s seven-point sensation scale. The measurement was carried out in transitional periods from the dry season to the wet season. Interpretation of graphs and charts was made for analysis based on the variable of effective temperature. The results of the research indicated that there was a connection between effective temperature and TSV. The effective temperature in vernacular houses in tropical mountain locations tended to be lower, and therefore the cool thermal sensation had the greatest percentage of TSV. Meanwhile, the effective temperature in tropical beach locations tended to be high, and therefore the warm thermal sensation had the greatest percentage. In a neutral scale, the percentage of TSV in tropical mountain locations was greater than that of TSV in tropical beach locations. Therefore, it is concluded that the occupants of vernacular houses in tropical mountain location felt more comfortable than those of vernacular houses in tropical beach locations.

On a new generalization of Jacobsthal quaternions and several identities involving these numbers

In this paper we generalize Jacobsthal quaternions to \((s,p)\)\dywiz Jacobsthal quaternions. We give some of their properties, among others the Binet formula, the generating function and the matrix representation of these quaternions. We will show how a~graph interpretation can be used in proving some identities for quaternions.

Compreensões sobre gráficos por professores de escolas no campo

A interpretação de dados estatísticos apresentadas em gráficos vincula-se a competências que devem ser desenvolvidas pelos cidadãos no decurso de sua escolarização. No Brasil os contextos de Educação do Campo são desafiadores uma vez que essa modalidade de demanda que sejam consideradas as especificidades dos contextos campesinos. Este artigo discute aspectos de uma pesquisa que investigou as compreensões sobre gráficos que professores de escolas no campo evidenciaram a partir de entrevistas e oficinas de formação continuada sobre letramento estatístico. Os resultados obtidos das entrevistas evidenciaram algumas lacunas em relação às concepções de Educação do Campo, bem como evidenciou dificuldades quanto a compreensão dos gráficos propostos para interpretação. As oficinas de formação mostraram-se como espaços importantes de formação para o letramento estatístico, pois os professores sentiram-se incentivados a enriquecer sua prática pedagógica.