Time Use

It is increasingly acknowledged that behaviour change is required for a reduction in energy demand, as technological innovation is unlikely to deliver change at an adequate scale and speed. However, a review of energy policy  documents  shows that the implications of behaviour change for the timing of energy demand are generally overlooked and/or taken for granted. In the transport sector, for example, much policy and research effort has focused on achieving a shift from current energy-demanding, carbon-intensive and car dependent travel patterns to 'greener' modes such as public transport and active travel. However, different transport modes are likely to correspond to rather different ways of incorporating activities in the daily- and weekly-schedule, and this has been poorly taken into account. This is problematic since both a significant modal shift and the electrification of the vehicle fleet are likely to have serious implications for issues of peak-demand on the electricity grid. On the other hand, entrenched ways of scheduling activities might be an important reason for the reluctance of households to 'give up the car'. Indeed, car use is often considered to be more 'convenient' because it allows flexible, spontaneous and frequent travel at any time of day. In other cases, however, it might allow households to concentrate activities in time. The case of food shopping provides a clear illustration of this. Indeed, the car allows shoppers to carry more (heavy) goods with them. This in turn makes it possible to reduce the number of shopping runs to a single (bi-) weekly 'bulk shopping' trip, possibly on weekends and to a larger and more distant supermarket. By contrast, it is reasonable to assume that non-car users do smaller and more frequent runs to nearby shops. While these arguments are appealing, there is currently only limited quantitative evidence on this relationship. In this paper we aim to fill this gap, based on a secondary analysis of the latest release of the National Travel Survey (NTS), that includes a one-week travel diary for a representative sample of the British population. We use various data analysis techniques  to assess how the timing and frequency of food shopping vary according to transport mode. The findings provide broad support for the initial hypothesis, but interestingly also suggest a more nuanced view of the temporalities of food shopping. We conclude by reflecting on the implications of these findings for sustainable transport policies aiming to modal shift and the diffusion of electric vehicles. Finally, on a theoretical level, we suggest that crucial factors such as timing and the portability of objects are overlooked in behaviourist approaches to sustainability. As an alternative, we discuss our results in the context of sustainable practice theories, where such factors are better taken into account.

There are three main understandings of the notion of 'car dependence' in transport research: a micro-social understanding (dependence as an attribute of individuals), a macro approach (attribute of societies or local areas as whole), and a meso-level understanding, where it refers to trips – or rather to the activities that people need to travel to. While the first two approaches have been dominant, in this paper I further develop the third. At the theoretical level, I build on theories of social practice to put forward the notion of ‘car dependent practices’, defined as those where the car is an essential element in the integration between different elements (materials, competences and meanings, as well as timing and location) and modal shift would entail substantial adjustments in their relationship. While a thorough study of practices requires qualitative methods, in this paper I explore the suitability of innovative sequence analysis techniques to further knowledge in this field. I apply the sequence pattern mining and clustering tools of the Visual-TimePAcTS software to the 2000 British Time Use Survey dataset, in order to bring to light traces of car dependent patterns of activities in daily life. The paper presents the preliminary results of this empirical study, carried out in the context of Theme 1 (Trends and Patterns in Energy Demand) of the DEMAND (Dynamics of Energy, Mobility and Demand) Research Centre.

"Abstract: The use of time by university students is one of the most relevant inputs to their education process. However, previous empirical evidence has produced contradictory results, which could be attributed to several factors such as the levels of disaggregation and types of academic and non-academic activity considered, discrepancies in the methods for obtaining information (diary as opposed to survey) or a lack of qualitative focus in relation to the use of time (study habits). In this study, we introduce an additional explanatory variable which is the condition on female or male of the student. Thus, the objective of this research is to analyze the organization of students’ time, trying to establish whether there are some distinct patterns for men and women, and the impact of the allocation of time on their academic results, trying to find specific gender behaviors. Our results highlight the existence of differences between men and women in the distribution of their time on academic and non-academic activities, being higher the time dedicated to the first activities in the case of women, particularly in activities related to self-study. However, this higher time dedication does not translate into better academic performance, showing, first, the negative impact of being woman on academic outcomes and, second, the lower profitability of the time spent by women in relation to time invested by men. Good study habits, that is, the quality of time spent, are particularly significant to improve academic performance for female students.

Resumen: El uso del tiempo por parte de los estudiantes universitarios es uno de los inputs más relevantes a la hora de determinar sus resultados académicos. Sin embargo, las evidencias empíricas previas encuentran resultados contradictorios, que podrían ser atribuibles, en parte, a los niveles de desagregación y tipos de actividades académicas consideradas, a las discrepancias en los métodos de obtención de información (diario frente encuesta) o la falta de un enfoque cualitativo en relación con el uso del tiempo (hábitos de estudio). En este estudio se introduce una variable más a tener en consideración y es la condición de mujer u hombre del estudiante. Así, el objetivo de esta investigación es analizar la organización del tiempo de los estudiantes, tratando de establecer si existen unos patrones diferenciados para estudiantes mujeres y hombres, así como el impacto de esa distribución del tiempo sobre sus resultados académicos, intentando encontrar comportamientos específicos en función del género. Los resultados obtenidos permiten constatar la existencia de diferencias entre mujeres y hombres en la distribución de su tiempo en actividades académicas y no académicas, siendo mayor la dedicación académica relativa de las mujeres, particularmente en actividades vinculadas al estudio autónomo. Esa mayor dedicación no se traduce en mejores rendimientos académicos, poniendo de manifiesto, por un lado, el impacto negativo de la condición de ser mujer sobre los resultados académicos y, por otro, la menor rentabilidad del tiempo invertido por las mujeres en relación con el invertido por los hombres. Frente a la cantidad de tiempo, para el colectivo femenino, unos buenos hábitos de estudio, esto es la calidad del tiempo invertido, sí resultan particularmente significativos para mejorar los rendimientos académicos."

The DEMAND Research Centre (Dynamics of Energy, Mobility and Demand) focuses on ‘what energy is for’, i.e. on the social practices that lead us to consume large (and often increasing) amounts of energy and greenhouse gases emissions. In this context, the contribution of CTR Aberdeen is to focus more specifically on trends and patterns in travel-related energy demand. The goal is to reconceptualise mobility practices and to study their rhythms with a quantitative approach, using innovative data analysis techniques applied to large existing datasets (time use and national travel surveys). The seminar reports on this work in progress, and it is structured in two parts. First, I introduce the concepts of social practice and meso-level car dependence, and discuss their role in guiding the empirical work. Second, I present the research strategy and initial findings of two empirical studies. The first aims to identify traces of mobility intensive and/or car dependent practices applying sequence visualization and pattern mining techniques to UK 2000 Time Use Survey data. The second study focuses on a specific car dependent activity – food shopping. The goal is to test the hypothesis that the weekly rhythms of food shopping travel are significantly different depending on car availability and use (weekly 'bulk shopping' trip for car users vs. smaller and more frequent runs to nearby shops for others). This will be accomplished by applying two-stage optimal matching to the 7-day travel diary of the British National Travel Survey. This approach is meant to challenge current modal shift policies, which overlook the temporalities associated with different activity/mode combinations.

"It is increasingly important to know about when energy is used in the home, at work and on the move.  Issues of time and timing have not featured strongly in energy policy analysis and in modelling, much of which has focused on estimating and reducing total average annual demand per capita.  If smarter ways of balancing supply and demand are to take hold, and if we are to make better use of decarbonised forms of supply, it is essential to understand and intervene in patterns of societal synchronisation. This calls for detailed knowledge of when, and on what occasions many people engage in the same activities at the same time, of how such patterns are changing, and of how might they be shaped.  In addition, the impact of smart meters and controls partly depends on whether there is, in fact scope for shifting the timing of what people do, and for changing the rhythm of the day.  Is the scheduling of daily life an arena that policy can influence, and if so how? The DEMAND Centre has been linking time use, energy consumption and travel diary data as a means of addressing these questions and in this working paper we present some of the issues and results arising from that exercise. 
See paper online at http://www.demand.ac.uk/wp-content/uploads/2014/02/The-timing-and-societal-synchronisation-of-energy-demand-for-web-1.pdf"

Using detailed time-use data from 2002-03 and 2009-10 for Spain, we analyze changes in the time-allocation decisions of the Spanish population, with a focus on the time devoted to total work. Consistent with prior literature, we document that the concept of “iso-work” (e.g., the time devoted to total work by gender is equal) does not hold in societies with stringent gender roles, such as Spain. Women devote more time to total work than men, and this difference has increased throughout the period studied by 2 hours per week. The relative increase in total work for women compared to men can be explained by a relative increase in market work of 8 hours per week, coupled with a relative decrease in non-market work of 6 hours per week, which have led Spanish women to devote, relatively, 2 fewer hours to leisure per week in 2009-10, compared to 2002-2003. We propose social norms as a potential explanation of these empirical findings. By uncovering how individuals allocate their time inside and outside of the market over a period of time, our results may improve our understanding of the dynamics of economic change and welfare

"It is increasingly important to know about when energy is used in the home, at work and on the move.  Issues of time and timing have not featured strongly in energy policy analysis and in modelling, much of which has focused on estimating and reducing total average annual demand per capita.  If smarter ways of balancing supply and demand are to take hold, and if we are to make better use of decarbonised forms of supply, it is essential to understand and intervene in patterns of societal synchronisation. This calls for detailed knowledge of when, and on what occasions many people engage in the same activities at the same time, of how such patterns are changing, and of how might they be shaped.  In addition, the impact of smart meters and controls partly depends on whether there is, in fact scope for shifting the timing of what people do, and for changing the rhythm of the day.  Is the scheduling of daily life an arena that policy can influence, and if so how?
The DEMAND Centre has been linking time use, energy consumption and travel diary data as a means of addressing these questions.  This seminar presents ideas and results from this aspect of the DEMAND Centre’s research and provides an opportunity to focus on the significance of timing and synchronisation for modelling, strategy, ‘behaviour change’ and policy analysis.
See presentation online at http://www.demand.ac.uk/15/01/2014/presentation-given-at-decc-10-december-2013/"

This paper analyzes the relationship between health status and the time devoted to both market and non-market work, by individuals responding to the Spanish Time Use Survey 2002-2003. We find that better health of individuals is associated with an increase in the hours of market work, while reducing the time devoted to non-market work. We show that OLS estimations yield biased results, and the use of instrumental variables (IV) is needed to deal with endogeneity issues.

""This paper analyzes the relationship between time allocation decisions of the unemployed, gender, and regional unemployment rates. Using two cross sections from the 2002–2003 and 2009–2010 Spanish Time Use Surveys, we find
that higher regional unemployment rates are associated with increases in the time devoted to study by men. Regional unemployment rates are also associated with more time devoted to household production, particularly for unemployed men and
women living in a couple, and to less time devoted to leisure, particularly for unemployed men with a working partner and unemployed women not living in a couple. We interpret our findings as evidence favoring consumption smoothing. Higher regional unemployment rates imply a lower availability of jobs for the unemployed, it reduces individual expectations of finding a job, and thus households may try to increase their time spent on household production to reduce market expenditures and thus maintain their consumption constant. Increases in the time
devoted to household production during business cycles need to be considered in the analysis of the wellbeing of the unemployed. Consumption smoothing may imply increased wellbeing, but more time devoted to household production is associated with lower experienced utility of individuals throughout the day.""

Using detailed time-use data for seven industrialized countries from the 1970s until today we document general decreases in men’s market work coupled with increases in men’s unpaid work and child care, and increases in women’s paid work and child care coupled with decreases in unpaid work. We also find almost universal increases in the time devoted to watching television over this period, and uncover a widespread increase in leisure inequality in favor of lower educated adults. Trends in leisure inequality mirror the general increase in income and earnings inequality experienced in most countries over this period, especially after the mid-1980s. All these findings are consistent with previous results for the US. However, in contrast to the increases in leisure found for the US, we fail to find common trends in leisure time across countries over the period analyzed.

""We analyse how self-employed and employed mothers allocate thei time throughout the day in order to balance their work and family responsibilities. To that end, we use time diary information from Spain, a country with a low level of women’s participation in the labour market (Spanish Time Use Survey (STUS), 2002–2003). We find that selfemployed mothers devote less time to market work, and more time to tertiary (e.g. sleeping, eating) and leisure activities, than employed mothers in a working day. We also find differences between employed and selfemployed mothers in the timing of market work, child care and housework
throughout the day, and we find complementarities between the timing of market work of working mothers and the timing of child care of their male partners. Our results on timing are consistent with the hypothesis that self-employment stands as a possible way for mothers to have greater control over the timing of work (flexible hours), and that they may therefore be able to work odd shifts, when the spouse is available to care for the children.""

""This paper examines the role of the doing-gender hypothesis versus traditional models of the household in explaining how the woman’s share of home labor varies with relative earnings. The findings, using the 2002–3 Spanish Time Use Survey (STUS; Spanish Statistical Office 2003), support the doing-gender hypothesis in the case of housework: a woman’s relative share of housework fails to decrease with her relative earnings beyond the point where her earnings are the same as her husband’s. In contrast, a woman’s share of childcare time displays a flat pattern over the distribution of her spouse’s relative earnings.
This last result is neither consistent with traditional theories of the household, nor with the doing-gender hypothesis. It can, however, still be interpreted in light of social norms, whereby women specialize in this type of caring activity regardless of their relative productivity or bargaining power.""

There is an extensive literature examining the relationship between elder care, child care and labour market activities, although these studies have largely overlooked their simultaneity. This article explores the relationship between these three activities, accounting for the influence that children have on parental allocation of time, using the 2002–2003 Spanish Time Use Survey (STUS). We find that the presence of children has quantitatively significant positive effects on the extent of dependent care-giving activities, with this increase in care-giving being compensated for by a decrease in the time devoted to the labour market.

Levels of time stress have increased markedly over the last 30 years, affecting well-being. Self-employment is viewed as allowing the individual greater autonomy and more flexible hours, which may reduce time stress. This article analyses time stress of the self-employed, compared to the employed, using the Spanish Time Use Survey (2002/03) finding that, when objective indicators of time allocation are included, being selfemployed increases the time stress perceived by men, with our interpretation being based on the notion that not only the quantity but also the quality of leisure matters.

We analyze the causal effect of the length of the worker’s commute on worker's productivity, by examining whether commuting time has any effect on worker's labour market supply. Using the Spanish Time Use Survey 2002-03, our GMM/IV estimation yields a positive causal impact of commuting time on the time devoted to the labour market, with one hour of commuting increasing the time devoted to the labour market by 35 minutes in a working day. Our results shed light on the relationship between commuting and workers behaviour, since daily labour supply should be considered in theoretical models to provide a comprehensive view of commuter behaviour.