Electronic Supplementary Material 1

Survey Data

Survey data is used to inform the ABM presented here. As previously mentioned, the survey was administered to four major urban areas (Chicago, Houston, New York, and San Francisco), in order to obtain survey data relevant to the United States urban population as a whole. Survey participants were recruited by posting advertisements in the “ETC” section of Craigslist during the summer of 2012. Respondents received a ten dollar amazon.com gift code upon completion of the survey. The survey was conducted in accordance with the University of Illinois at Chicago Office for the Protection of Research Subjects protocol number 2012-0562. Responses were capped at 500 participants, and of those 476 surveys were found to be usable. The average daily hours of household light use was found to be approximately 9 hours. The demographics of the survey participants are presented as Table A1.

Table A1 Demographics of survey participants

Age / % of Respondents
Under 18 / <1
18 to 25 / 12
26 to 35 / 41
36 to 45 / 30
46 to 55 / 11
56 to 65 / 5
66 to 75 / <1
Over 75 / <1
Gender
Male / 49
Female / 51
Prefer not to answer / <1
Ethnicity
Caucasian (not of Hispanic origin) / 43
African American / 28
American Indian, Eskimo, Aleut / 4
Asian and Pacific Islander / 14
Hispanic (of any race) / 6
2 or more races / 4
Prefer not to answer / 1
Occupation
Homemaker or stay at home parent / 2
Employed / 89
Student / 6
Unemployed / 3
Educational Level Achieved
Less than high school or GED / 1
High school or GED / 3
Some college / 12
Associate’s degree / 9
Bachelor’s degree / 38
Post bachelor’s degree / 16

Survey participants were asked the primary lighting type in their household. Table A2 presents the responses.

Table A2 Primary household lighting type

Lighting Type / % of Respondents
Incandescent / 26
Fluorescent / 25
Compact Fluorescent Lamp (CFL) / 23
Light Emitting Diode (LED) / 23
Don’t Know / 3
Other / <1

The overall data were utilized to obtain the typologies and allocations presented in Table A3. The typologies were created utilizing a ranking question, where survey participants were asked to rank six characteristics (also presented in Table A3) of lighting in the order of which the characteristic influenced the consumer’s lighting choices. The responses were then allocated into six typologies dependent on what the survey respondents ranked as their most important factor. Then within each group, it was determined what factor the majority ranked as their second most important factor. That characteristic was then assigned to the typology as a whole as the second more important factor. This was continued for all of the factor and typologies.

The ranking of the factors by each typology was then used to generate a weighting for the utility equation, using the formula presented below as equation A1, where x is the factor ranking.

wi=7-xi6 (A1)

This results in a weight between 0 and 1, where the factor with the greatest weighting is 1.

The utility function is presented as equation 1, and includes the six factors discussed in Table 1. The scores of each factor are normalized between 0 and 1, using equation A2.

Fi=Value-MinMax-Min (A2)

The value is the factor of the lighting option being considered, the min is the minimum value of that factor among all three lighting options, and the max is the maximum value of the factor among all three lighting options. When the factor score is computed to be 0, a very small number (10-6) was utilized in the utility function, in for a single lighting characteristic not to exert undue influence over the utility function.

The factor values used for each light bulb are representative of a 60 watt equivalent incandescent, CFL, and LED lighting option. This data was retrieved from bulbs.com (2012), and is presented as Table A3.

Table A3 Lighting characteristics

Incandescent / CFL / LED
Price ($) / 1.17 / 1.59 / 33.99
Lifetime (hours) / 1,500 / 8,000 / 25,000
Wattage (W) / 60 / 13 / 12
Diameter (in) / 2.375 / 1.8 / 2.25
Length (in) / 4.440 / 4.9 / 4.25
Lumens (lm) / 830 / 825 / 800