Categorizing Pro-environmental Behaviors Using the Laypeople's Perspective

Most efforts to categorize pro-environmental behaviors (PEBs) have focused on researchers’ – rather than laypeople’s – perceptions of PEBs. Drawing on the psychometric paradigm used to categorize environmental risks, we aimed to identify the PEB attributes salient to laypeople and, from that, determine the underlying dimensions of PEB. In Study 1, participants (n = 157) evaluated 30 PEBs through open-ended questions. The results revealed 21 attributes that laypeople commonly associate with PEBs. In Study 2, 250 MTurk participants rated 74 PEBs on the 21 attributes. An exploratory factor analysis revealed four factors underlying PEB: Factor 1 (Financial and Behavioral Cost), Factor 2 (External Pressures), Factor 3 (Environmental Impact and Savings) and Factor 4 (Health and Safety Impacts). PEBs were characterized along each dimension and along multiple dimensions using biplots. Additionally, the four factors strongly predicted behavior intention. The results have implications for interventions to increase PEBs in the general public. Keywords: Pro-environmental behavior, factor analysis, perception, categorization CATEGORIZING PRO-ENVIRONMENTAL BEHAVIORS 1 Categorizing Pro-environmental Behaviors Using the Laypeople's Perspective Within the field of conservation psychology, researchers have sought to understand, explain, and predict behaviors that benefit the natural environment. There are a great number of pro-environmental behaviors (PEBs) to study – from carpooling and taking shorter showers to line-drying laundry and buying local produce. PEBs are not only innumerable but also diverse in what factors predict them. For example, factors that predict shutting down electronics at night differ from those that predict upgrading to energy-efficient appliances (Karlin et al., 2012; Nair, Gustavsson, & Mahapatra, 2010). While the manifold nature of PEB could make for some lengthy careers of those studying PEB, the threats associated with global climate change have placed ever-increasing pressure on researchers to test and identify effective strategies of fostering PEB in the general public. Such a difficult and time-sensitive task has called for the research field’s own efficiency upgrade. One way that researchers have sought to efficiently study PEB is by studying groups of similar behaviors. Classifying environmental behaviors into distinct categories allows for researchers to more adequately identify predictor variables of PEBs, though the current field of pro-environmental research lacks a common behavior categorization scheme. Understanding the similarities and distinctions between behaviors and what variables predict those behaviors is a necessary step for the development of effective intervention strategies that aim to reduce energy use (Karlin et al., 2012). Researchers have organized PEBs in several different ways, each with its own set of limitations. Three categorizations of PEBs exist that are most common in pro-environmental and energy conservation research: (1) domain-specific behaviors, (2) curtailment versus efficiency behaviors, and (3) intent-oriented versus impact-oriented behaviors. CATEGORIZING PRO-ENVIRONMENTAL BEHAVIORS 2 Domains of Environmental Behaviors Researchers have demonstrated that PEBs may cluster or group together in a way that reflects a shared purpose between behaviors (Stern, 2000; Whitmarsh & O’Neill, 2010). For example, recycling, composting, and buying products with less packaging may aggregate as waste reduction behaviors (Whitmarsh & O’Neill, 2010). National surveys from the early 1990s (i.e., 1993 General Social Survey and 1994 national environmental survey) provide support for the distinction between types of environmental behaviors. Factor analysis on self-reported behavior and behavioral intention measures indicated the existence of three factors: consumer/household behaviors, environmental citizenship behaviors (e.g. voting, writing to government officials), and policy support (see Dietz, Stern, & Guagnano, 1998 and Stern, Dietz, Abel, Guagnano, & Kalof, 1999). One behavior, activism, did not appear to load onto any factors in the 1994 study and has been interpreted as an independent type of environmentally significant behavior (Stern, 2000). From these results, Stern (2000) distinguished between four broad domains of behavior: activism, non-activist public-sphere behaviors, private-sphere behaviors, and other environmentally significant behaviors (Figure 1). Activism behaviors include active involvement in environmental organizations and participation in pro-environmental social movements while non-activist public behaviors include support for public policies (Stern, 2000). Stern (2000) proposed the subdivision of private-sphere behaviors into four subtypes based upon the type of decision involved: purchase of major household goods or services, use and maintenance of environmentally important goods, waste disposal, and green consumerism. Other environmentally significant behaviors include any behavior that influences the actions of organizations to which an individual belongs such as an employee beginning a composting program at work (Stern, 2000). CATEGORIZING PRO-ENVIRONMENTAL BEHAVIORS 3 More recently, Dietz, Gardner, Gilligan, Stern, and Vandenbergh (2009) divided household PEBs – a similar domain to Stern's (2000) private-sphere domain – into five categories: weatherization, energy-efficient equipment, maintenance, adjustments, and daily actions (Figure 2). Examples of weatherization actions include insulating one’s home attic, weather-stripping doors, and installing an energy-efficient home heating system. Energyefficient equipment actions are energy-efficiency upgrades such as purchasing a hybrid motor vehicle and installing an energy-efficient washing machine. Maintenance actions involve maintaining one’s energy equipment like getting an oil change and changing HVAC air filters. Adjustments actions are behaviors like setting one’s water heater temperature to 120 degrees F and using the cold rinse setting on one’s washing machine. Daily actions are daily behaviors ranging from turning off lights and shutting down computers at night to carpooling and chaining errand trips. Dietz et al. (2009) also defined these five categories in terms of attributes they considered relevant to behavior engagement, namely, behavior frequency and financial cost. In terms of behavior frequency, weatherization, energy-efficient equipment, and adjustments actions are one-time behaviors while maintenance actions require multiple instances but fewer than daily actions. In terms of financial cost, weatherization and energy-efficient equipment actions involve investments, maintenance actions have a low financial cost and, like adjustments and daily actions, sometimes have no financial cost. Other domain-specific PEB categorizations exist as well. In studying the relationships between pro-environmental behaviors and evaluating consistencies across behavior performance in a UK population, Whitmarsh and O’Neill (2010) used principal component analysis on selfreport measures of past behavior to categorize PEBs, which resulted in eight domains of environmental behavior: waste reduction (e.g., recycling, composting), eco-shopping and eating CATEGORIZING PRO-ENVIRONMENTAL BEHAVIORS 4 (e.g., buying organic foods, reducing meat consumption), regular water and domestic energy conservation (e.g., taking shorter showers, turning off lights not in use), one-off domestic energy conservation actions (e.g., installing renewable energy system), eco-driving (e.g., braking or accelerating gently), political actions (e.g., taking part in a protest about an environmental issue), reducing car use (e.g., using alternative transportation) , and flying (e.g., reducing amount of flying). Some behaviors, however, fell within multiple domains. For example using alternative transportation, correlated highly with both eco-driving and reducing car use, and recycling correlated with waste reduction and regular water and domestic energy conservation (Whitmarsh & O’Neill, 2010). While categorizing PEBs by domain has allowed researchers to simplify the wide variety of environmental behaviors, whether a behavior falls within a particular domain has been determined by either how frequently people report engaging in the behavior (Stern, 2000; Whitmarsh & O’Neill, 2010) or by a few behavior attributes, such as financial cost, considered relevant by researchers (Dietz et al., 2009). Though understanding how often people engage in certain behaviors and the financial cost of those behaviors has use for identifying behaviors that ought to be targeted for intervention, it does not provide much insight into the specific behavior characteristics that contribute to people’s decision to engage in PEB. Curtailment versus Efficiency Upgrades Rather than classifying PEB into several narrowly refined categories, many researchers have used a simple dichotomous classification scheme (Barr, Gilg, & Ford, 2005; Gardner & Stern, 2008; Inskeep & Attari, 2014; Karlin et al., 2012; Laitner, Ehrhardt-Martinez, & Mckinney, 2009). Two types of household energy-saving actions constitute this classification (Figure 3): efficiency-improving actions, which mostly involve purchases, and curtailment CATEGORIZING PRO-ENVIRONMENTAL BEHAVIORS 5 actions, which involve decreasing the use of existing energy equipment (Gardner & Stern, 2008; Karlin et al., 2012). Examples of curtailment behaviors include turning off lights when not in use and reducing shower time. Under the domain-specific categorization by Dietz et al. (2009) these behaviors are daily actions. Marked by the need for financial investment, efficiency behaviors include purchasing and installing solar panels as well as upgrading to energy-saving appliances. Many efficiency actions fall into the domain of one-off domestic energy conservation actions proposed by Whitmarsh and O’Neill (2010), as well a