Social scientists have developed a variety of methods that are capable of assessing all four classifications of value with varying degrees of quantification. Clearly, this literature is far too extensive to be discussed in any detail. Rather, we briefly summarize some available methods in an attempt to give a flavor of the range of techniques available to assess values, with key references to the literature.
Some methods have rigorous conceptual foundations for value, whereas others are indicators of value, rather than measures of value. All methods have limitations. Commonly, methods with greater conceptual rigor might be more capable of providing quantitative measures of value, which are more easily incorporated into management decisions. However, these approaches might not be as appropriate when applied to values that are less tangible in nature and therefore inherently less quantifiable. In contrast, qualitative methods may be more pertinent to characterizing these latter types of value, but it may be more difficult to use these qualitative assessments to support practical management decisions.
Planning and architects
Community planners, landscape architects, and site designers sometimes use systematic methods of eliciting and assessing the values of a given community or user group. Such methods include visual preference surveys that measure individual preferences for different landscapes, architectural styles, or visual attributes of natural features such as a lagoon (e.g., Ryan 2005). A related method is visualization or visual impact assessment, through which potential changes to a given landscape are modeled via graphic simulation as a means of helping a community evaluate different planning or development scenarios (Berke et al. 2006). One example would be to show visualizations depicting how a lagoon is projected to change through natural processes and what the lagoon would look like under alternative development scenarios or alternative policies.
Charrettes are collaborative public workshops that use an interactive approach to elicit values (Berke et al. 2006, National Oceanic and Atmospheric Administration Coastal Services Center 2007). Issues and concerns raised in charrettes are used to identify important stakeholder values, thereby making social values an integral part of the planning process. Charrettes also improve stakeholder communication, which can aid in developing a shared vision and building consensus. Charrettes are used primarily to engage interested parties in a decision-making process, but do not usually produce quantitative assessments of value. Thus, this method of assessing values is primarily qualitative.
Economic methods of valuation are based on a rigorous conceptual foundation of individual preferences. Although economic values are most commonly expressed in dollar terms, economic theory also provides relative preferences over commodities (e.g., Mazzotta et al. 1994). The two primary methods for assessing economic values can be categorized into revealed preference methods and stated preference methods (e.g., Freeman 2003). Revealed preference approaches are based on inferring value from actual choices made by people, typically within market contexts (e.g., Just et al. 2004). Early work in revealed preference methods was based on valuing “consumer’s surplus,” or the excess in value above and beyond the purchase price of an object. Environmental economists extended market-based approaches to include “related markets” approaches such as the travel cost method or the hedonic price method (e.g., Freeman 2003). Related markets approaches are applied when a commodity such as a recreational fishing trip to a lagoon is not directly sold in the marketplace. Instead, a closely related “good” is used to estimate cost. For example, the travel cost approach uses the cost of accessing a recreational site as the price of “purchasing” the recreational activity. This cost is used as a substitute for the market price for the commodity. The value of a recreational experience is inferred by observing how participation rates vary as the cost of participating varies. The hedonic price approach relates the purchase price of a commodity such as a house to the environmental amenities in the surrounding area. If housing buyers desire high levels of environmental quality such as views of a pristine lagoon, they will be willing to pay more for a house located on such a site compared to a house that is identical in all ways but is located on a site with lower environmental quality such as one without a view of a lagoon. The additional amount that consumers are willing to pay to live on a site of higher environmental quality is indicative of one component of the value of improved quality, i.e., that accruing to local homeowners.
Stated preference methods are typically survey based, and respondents are asked a series of hypothetical questions that are used to infer values (e.g., Mitchell and Carson 1989). State-of-the-art surveys are developed and pre-tested with extensive use of focus groups, which are used to identify what potential respondents understand about the stated commodity, what information they require to provide meaningful answers, and what is the most effective format and wording for questions (Desvousges and Smith 1988).
Early stated preference methods were based on the so-called contingent valuation method, which is a direct questioning approach in which the survey determines the maximum amount of money the respondent would pay for some stated commodity (e.g., Davis 1963, Randall et al. 1974). For example, a survey may be conducted to measure an individual’s willingness to pay for being able to take walks around a lagoon. Later applications of contingent valuation techniques include referendum-based approaches in which individuals are asked whether they would vote for a hypothetical program to provide some stated commodity at a stated price. For example, respondents might be asked whether they would vote for or against a program to restore eelgrass in a lagoon at some indicated cost to them, often in terms of higher taxes.
“Choice-based” economic valuation methods lay out a series of two or more options, described in terms of a set of characteristics, and ask respondents to indicate which option they would select (e.g., Adamowicz et al. 1998). For example, a choice-based survey might ask respondents whether they would choose a program to protect a stated lagoon ecosystem at a given cost, or whether they would prefer an alternative program that might restore damaged wetlands. Statistical methods are used to determine how each characteristic affects the likelihood that individuals select an alternative, thereby providing a quantitative measure of the relative importance that the individuals place on each characteristic. This allows researchers to calculate relative values of different attributes. If the cost of the alternative is one attribute, then the researchers can calculate the implicit monetary value of the attributes, i.e., the relative value of a unit increase in the attribute versus a unit increase in cost. For example, if the commodity in question is a recreational fishing trip and two attributes are the catch rate and the cost of participating, the approach can be used to estimate the rate at which individuals are willing to trade off increased cost for increased catch rate, giving the dollar value of increased recreational catch.
In principle, stated preference methods can be used to calculate values associated with virtually any commodity, including values that are normally thought to be difficult or impossible to monetize. In practice, of course, valuation is complicated by issues such as the hypothetical nature of the transaction and the lack of knowledge about, or experience with, the commodity in question (e.g., Mitchell and Carson 1989).
Sociology and psychology
Social and psychological valuation methods characterize values using individuals’ expressions of the relative importance of different amenities. These are primarily qualitative methods that are most typically based on ordinal rankings (most important vs. less important) or rough interval-scale measures of differences in assessed values. These methods are generally implemented using interview techniques such as individual narratives, semi-structured interviews, or formal surveys (e.g., Brandenburg and Carroll 1995, Wengraf 2001).
A range of tools are used to analyze interviews. For example, content analysis systematically identifies keywords and causal structures in written or spoken text based on the assumption that the most commonly used words, phrases, and ideas in a communication reflect the most important considerations (e.g., Krippendorff 2004). A researcher might ask a series of open-ended questions to homeowners to identify the most important values that they hold for a lagoon. The responses could be analyzed using content analysis to identify the number of times certain words, phrases, or concepts are mentioned. The researcher then assumes that the values that are referred to a large number of times are most important, whereas values that are rarely or never mentioned are less important. Formal surveys commonly use Likert scales to identify the strength of agreement that respondents have to a set of statements. For example, one statement in a survey might say “I enjoy living near a lagoon because I am inspired by the beautiful views,” and respondents would indicate the extent to which they agree with the statement on a five-point scale ranging from “strongly agree” to “strongly disagree.” Responses can be used to calculate an index or scale that measures the relative importance of different values associated with the lagoon.
Social/civic valuation is used to measure values that groups place on amenities. For example, the results of an actual public referendum might be used to determine if the majority of voters feel that protecting a lagoon is worth what it will cost to do so. Questionnaires are sometimes used as a follow up to a referendum to get additional information.
Alternatively, hypothetical questions are sometimes posed to groups to elicit civic values. For example, focus groups might be convened to discuss lagoons to obtain a better understanding of the values that participants hold for lagoons. However, given the small number of participants, focus group are not typically used to assess values per se, but rather are more commonly used to identify the value or suite of values that may be most important. Focus groups might also be used as a preliminary stage in the development of a more rigorous method of eliciting values such as a survey. “Citizen juries” comprising representative members of the public could be presented with extensive information on the ecosystem functions and services associated with coastal lagoons (e.g., Brown et al. 1995). Juries are then asked to deliberate to decide whether it is worthwhile to carry out a program to protect or restore a lagoon, with a particular outcome being achieved at a stated cost to the community.
Decision scientists have developed a host of methods to help improve decision making. One method for eliciting values is multiattribute utility (MAU) theory, which is based on the notion that in complex and unfamiliar situations, values are constructed as part of the decision process (Keeney and Raiffa 1993). MAU theory attempts to simplify the cognitive task of constructing values by using an intensive survey approach that probes the decision maker with carefully structured questions that require a respondent to trade off characteristics against each other, thereby eliciting importance ranks and weights.