Seeing Missing Values

A Strategy for Automating the Presentation of Statistical Graphics for Users without Data Visualization Expertise - A Position Paper

The Relationship between Fatigue in Mothers and the Age of Their Less-Than-24-Month-Old Newborns

The birth of a child marks the beginning of a new developmental period for the parents. These changes have positive but also negative aspects, such as the increase in fatigue experienced by mothers during this period of time, which can be very limiting and lead them to postpone other life or work goals. However, despite the widespread nature of this problem, there is a lack of information about the duration of this fatigue, with estimates ranging from three months to six years

Automating statistical diagrammatic representations with data characterization

The search for an efficient method to enhance data cognition is especially important when managing data from multidimensional databases. Open data policies have dramatically increased not only the volume of data available to the public, but also the need to automate the translation of data into efficient graphical representations. Graphic automation involves producing an algorithm that necessarily contains inputs derived from the type of data. A set of rules are then applied to combine the input variables and produce a graphical representation. Automated systems, however, fail to provide an efficient graphical representation because they only consider either a one-dimensional characterizat…

Graphical User Interfaces for R

Since R was first launched, it has managed to gain the support of an ever-increasing percentage of academic and professional statisticians. However, the spread of its use among novice and occasional users of statistics have not progressed at the same pace, which can be attributed partially to the lack of a graphical user interface (GUI). Nevertheless, this situation has changed in the last years and there is currently several projects that have added GUIs to R. This article discusses briefly the history of GUIs for data analysis and then introduces the papers submitted to an special issue of the Journal of Statistical Software on GUIs for R.

Using Interactive Graphics to Teach Multivariate Data Analysis to Psychology Students

This paper discusses the use of interactive graphics to teach multivariate data analysis to Psychology students. Three techniques are explored through separate activities: parallel coordinates/boxp...

Graphical User Interfaces for R

Since R was first launched, it has managed to gain the support of an ever-increasing percentage of academic and professional statisticians. However, the spread of its use among novice and occasional users of statistics have not progressed at the same pace, which can be attributed partially to the lack of a graphical user interface (GUI). Nevertheless, this situation has changed in the last years and there is currently several projects that have added GUIs to R. This article discusses briefly the history of GUIs for data analysis and then introduces the papers submitted to an special issue of the Journal of Statistical Software on GUIs for R.

Under-reporting bicycle accidents to police in the COST TU1101 international survey: Cross-country comparisons and associated factors

Police crash reports are often the main source for official data in many countries. However, with the exception of fatal crashes, crashes are often underreported in a biased manner. Consequently, the countermeasures adopted according to them may be inefficient. In the case of bicycle crashes, this bias is most acute and it probably varies across countries, with some of them being more prone to reporting accidents to police than others. Assessing if this bias occurs and the size of it can be of great importance for evaluating the risks associated with bicycling.This study utilized data collected in the COST TU1101 action "Towards safer bicycling through optimization of bicycle helmets and us…

Seeing Frequency Data

Seeing Univariate Data

Psychosocial factors associated with helmet use by adult cyclists

Abstract: This study examines beliefs about helmet use in adult cyclists from 17 countries participating in the COST Action TU1101 Project (Helmet Optimization in Europe – HOPE). A total of 5797 respondents were included in the analysis after applying eligibility criteria and data cleaning. Cyclists' beliefs were assessed by 25 items using a 7-point Likert scale. These items were factor analyzed resulting in a four-factor solution (Factor 1: Perceived Benefits and Risk Reduction, Factor 2: Perceived Disadvantages and Barriers to Helmet Use, Factor 3: Perception of Group Norms, and Factor 4: Situation-Dependence of Helmet Use). Results show that both beliefs and helmet wearing behavior diffe…

Proposal of geographic information systems methodology for quality control procedures of data obtained in naturalistic driving studies

The primary goal of naturalistic driving studies is to provide a comprehensive observation of the driver's behaviour under real-life conditions by measureing a great number of parameters at high temporal frequencies. Achieving this goal, however, is a complex endeavor that faces many challenges such as the complexity of the vehicle instrumentation during the phase of data collection, and the difficult handling of large data volumes during the phase of data analysis. These drawbacks often cause episodes of data losses. Improving the technical aspects of the collection of naturalistic data is of paramount importance to increase the return of the investment made in it. An aspect to consider is…

Seeing Multivariate Data

Identifying critical incidents in naturalistic driving data: experiences from a promoting real life observation for gaining understanding of road user behaviour in Europe small‐scale field trial

The methodology of naturalistic driving observation aspires to observe the driver and his environment while driving in natural driving settings. It is of great importance in research on road safety as this method of observing road users eliminates the disadvantages of traditional methods like simulator studies or interviews. However, it produces vast such amounts of data and challenges data reduction and data analysis. Therefore automatic methods for filtering critical incidents based on thresholds for numerical data are often applied to select the data to be analysed. This study reports a small-scale field trial in Valencia, Spain, which was conducted within the promoting real life observa…

Why women do not use the helmet when riding a bicycle

Women seem to use the helmet when riding a bicycle less frequently than men. Two possible explanations for this behavior are that 1) it is less appalling to them because of lack of comfort or other reasons, or 2) they use bicycles in a more cautious way than men so they feel that they do not need the helmet as much. The present paper explores these two explanations in 5,691 cyclists that responded to an online survey conducted in 17 countries as part of an EU COST project. Answers to questions related to the two aforementioned explanations were analyzed graphically and three questions that showed the most conspicuous differences between males and females were identified. These were: ‘Helme…

Chronic, but not acute, fatigue predicts self-reported attentional driving errors in mothers attending infant children

AbstractMothers attending infant children usually experience high levels of fatigue, and fatigue has been shown to be related to car crashes through attentional errors, among other causes. The current study investigates the effects of fatigue on the attentional errors while driving of women attending infant children. A sample of 112 women—67 attending infant children and 45 not attending—filled out self-report questionnaires assessing acute fatigue, chronic fatigue, and attention-related driving errors. A mediational analysis showed that women attending infant children had higher levels of fatigue, and that chronic fatigue, but not acute fatigue, was related to attentional errors while driv…

Keep calm, pay attention, and carry on: Anxiety and consciousness mediate the effect of, mindfulness on driving performance in young drivers

Abstract Road traffic crashes are currently one of the main causes of deaths in the world and many efforts have been made to develop effective interventions to reduce them. Mindfulness has risen as a method for improving mental and physical well-being and has been hypothesized as potentially beneficial for driving performance. This has led to some commercial ventures based on such hypothesis, despite that the empirical evidence backing up them is still limited. Besides, at the moment there is not yet a clear account of the specific mechanism underlying this proposals. So, it seems plausible that the relationship between mindfulness and driving performance is indirect, and that personality t…

Conspiracy Beliefs Are Related to the Use of Smartphones behind the Wheel

The belief in conspiracy theories predicts behaviors related to public health such as the willingness to receive vaccines. This study applies a similar approach to an aspect of road safety: the use of smartphones while driving. A representative sample of 1706 subjects answered a series of questions related to what can be regarded as erroneous or conspiracy beliefs against restricting or banning the use of smartphones while driving. The results show that those having such conspiracy beliefs reported a greater use of smartphones behind the wheel.

Visualizing categorical data in ViSta

The modules in the statistical package ViSta related to categorical data analysis are presented These modules are: visualization of frequency data with mosaic and bar plots, correspondence analysis, multiple correspondence analysis and loglinear analysis. All these methods are implemented in ViSta with a big emphasis on plots and graphical representations of data, as well as interactivity for the user with the system. These provide a system that has shown to be easy, useful, and powerful, both for novice and experienced users.

Is naturalistic driving research possible with highly instrumented cars? Lessons learnt in three research centres.

This paper provides an overview of the experiences using Highly Instrumented Cars (HICs) in three research Centres across Europe; Spain, the UK and Greece. The data collection capability of each car is described and an overview presented relating to the relationship between the level of instrumentation and the research possible. A discussion then follows which considers the advantages and disadvantages of using HICs for ND research. This includes the obtrusive nature of the data collection equipment, the cost of equipping the vehicles with sophisticated Data Acquisition Systems (DAS) and the challenges for data storage and analysis particularly with respect to video data. It is concluded th…

Human‐centred design and assessment of information technologies in traffic

It is not without amusement that we sometimes notice how dangerously some in-vehicle technologies were regarded in the past, and that are now are seen as innocuous. Radios in cars, for example, were deemed such a source of dangerous distraction when they were introduced that it was proposed to ban them in some states of the US. Fortunately, nowadays, we can behold these old views as very naive, as it has been clearly demonstrated that they were completely unfounded - or has it?

Interfaces and Environments

Geo‐referencing naturalistic driving data using a novel method based on vehicle speed

Naturalistic driving is an experimentation model that allows us to recognise the driving modes observing the driver's behaviour at the wheel of a set of people in natural conditions during long periods of observation. This research methodology aims at increasing the representativeness of the data collected in opposition to data stemming from highly controlled laboratory experiments. However, naturalistic driving research designs produce large volumes of data that are difficult to handle. Thus, it is very important to work with suitable methods for representing and interpreting data, allowing us to observe the variability of the results. The aim of this study is to implement a new methodolog…

The History of ViSta: The Visual Statistics System

ViSta is a project that focuses on dynamic and interactive graphics for statistics and was initiated by the late Forrest W. Young at the beginning of the 1990s. For over approximately 20 years, Forrest and other collaborators, including the authors of this article, have used ViSta for experimenting with these kinds of graphics in different settings, applying them to different scenarios of data and statistical analysis, searching to develop the right combination of features most appropriate in each case. In this time, ViSta evolved quite considerably, going through what we reckon were three different stages, namely: the initial one setting forth the foundations of ViSta; the second period wh…

Gossip: The Architecture of SpreadPlots

A spreadplot is a visualization that simultaneously shows several different views of a dataset or model. The individual views can be dynamic, can support high-interaction direct manipulation, and can be algebraically linked with each other, possibly via an underlying statistical model. Thus, when a data analyst changes the information shown in one view of a statistical model, the changes can be processed by the model and instantly represented in the other views. Spreadplots simplify the analyst's task when many different plots are relevant to the analysis at hand, as is the case in regression analysis, where there are many plots that can be used for model building and diagnosis. On the othe…

Abiding by the law when it does not exist: The case of the helmet bicycle law

To improve the safety of bicycle users, some countries have enacted, or considered enacting, mandatory helmet legislation. Of course, the enactment of such legislation in a country assumes that its citizens will be well-informed of it, and consequently, will use the helmet more frequently than before. However, in the survey described in this paper we found that many people are not aware of the legislation in force in their own country, or, even if they know, they may not necessarily behave as dictated by the law. Thus, the effects of mandatory helmet legislation may be somewhat different than desired or expected. Therefore, the goal of this paper is to ascertain the role of cyclists' knowle…

The Scree Test and the Number of Factors: a Dynamic Graphics Approach

Exploratory Factor Analysis and Principal Component Analysis are two data analysis methods that are commonly used in psychological research. When applying these techniques, it is important to determine how many factors to retain. This decision is sometimes based on a visual inspection of the Scree plot. However, the Scree plot may at times be ambiguous and open to interpretation. This paper aims to explore a number of graphical and computational improvements to the Scree plot in order to make it more valid and informative. These enhancements are based on dynamic and interactive data visualization tools, and range from adding Parallel Analysis results to "linking" the Scree plot with other g…

Seeing Bivariate Data

Tools and Techniques

Dynamic-Interactive Graphics for Statistics (26 years later)

This paper briefly reviews the history of dynamic-interactive graphicsfor statistics, introduces an example of such graphics, and provides a fewglimpses as to the current state of things and the future trends we envision.The general conclusion is that dynamic-interactive graphics for statistics arethriving more than ever as they shift from the desktop to the internet. Thus,dynamic-interactive graphics are becoming increasingly important as they: 1) provide non-experts in statistics with the means to carry out analyses on their own; and 2) teach the basic concepts of statistics to students and practitioners with low to moderate  mathematics skills. Their increasingpopularity makes the lesson…

Visualizing parameters from loglinear models

This paper presents a graphical display for the parameters resulting from loglinear models. Loglinear models provide a method for analyzing associations between two or several categorical variables and have become widely accepted as a tool for researchers during the last two decades. An important part of the output of any computer program focused on loglinear models is that devoted to estimation of parameters in the model. Traditionally, this output has been presented using tables that indicate the values of the coefficients, the associated standard errors and other related information. Evaluation of these tables can be rather tedious because of the number of values shown as well as their r…

Mindfulness, inattention and performance in a driving simulator

The following study will explore the link between mindfulness, driver inattention and a number of driving performance variables that were tested using the SIMUVEG driving simulator. 67 subjects between the ages of 19 and 27 completed the mindful attention awareness scale, attention-related driving errors scale and attention-related cognitive errors scale questionnaires, and were evaluated in two driving performance measures: time to line-crossing and mean speed. The results did not show a correlation between driving performance and mindfulness measures; they did show low but significant correlations with driver inattention measures. A regression analysis suggested that the specific measure …