At the end of the two weeks, an online questionnaire was sent to the occupants of the building (Appendix I). To get a demographic overview of the participants, questions related to their status, age and country of origin were asked. Then, respondents were asked whether they had looked at the interface over the course of the trial. Those who replied negatively were led to a question asking about the reasons for their lack of interaction with the interface. Those that answered positively had access to the rest of the questionnaire. This included questions regarding the information provided by the interface, the number of times they checked it during the trial, their impressions regarding its use and design and suggestions to improve it.
The impact of the interface was then assessed through questions regarding the evolution of participants’ awareness of the building’s water consumption and knowledge of environmental and water issues. The features that were used the most were assessed based on users’ report of their use of the interface. Individuals were also asked whether they remember some of the tips and advice provided. To verify whether they did remember, those who responded positively had to write down one of the tips provided during the two weeks. Additionally, in order to understand the potential use of such an interface in a domestic environment, respondents’ willingness to use this kind of device at home and to invest in it was evaluated. Finally, it was necessary to assess participants’ general use of technologies as it could potentially influence their use of the interface. Therefore, in accordance with the Technophilia scale, participants had to assess a number of affirmations on a 5-point Likert scale ranging from ‘strongly agree’ to strongly disagree’[483]. They also had to report whether or not they considered themselves as being ‘technophobic’. To gain more in-depth knowledge about the use and impact of the interface, respondents to this questionnaire were asked to provide their email address if they wanted to take part in a focus group to share their experience of the interface. The focus group was conducted a week after the end of the trial.
7.3.2.1. Demographics
Eleven individuals filled in the post-trial questionnaire. These participants mainly come from Europe (72.7%). The rest of them is originally from China (9.1%), Sri Lanka (9.1%) and Saudi Arabia (9.1%). 54.5% are aged between 20 and 25 years old, 18.2% between 26 and 35 years old, 18.2% between 36 and 45 and one participant is over 46. Overall, the average
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Technophilia score among participants is high (42.3) and suggest that participants are very familiar with the use of technology [483].
Table 7-5. Percentage and grade point average of Technophilia items (post-trial questionnaire in office setting).
Items – Do you agree or disagree that SA A NAD D SD GPA
1. Technology is my friend 81.8 18.2 0 0 0 4.81
2. I enjoy learning new computer programs/apps and
hearing about new technologies 72.7 27.3 0 0 0 4.73 3. People expect me to know about technology and I
don't want to let them down 18.2 36.4 36.4 9.1 0 3.63 4. If I am given an assignment that requires that I learn
to use a new program or how to use a machine, I usually succeed
54.5 36.4 9.1 0 0 4.45
5. I relate well to technology and machines 54.5 36.4 9.1 0 0 4.45 6. I am comfortable learning new technology 63.6 36.4 0 0 0 4.64 7. I know how to deal with technological malfunctions or
problems 27.3 27.3 45.5 0 0 3.82
8. Solving a technological problem seems like a fun
challenge 18.2 36.4 18.2 27.3 0 3.45
9. I find most technology easy to learn 36.4 54.5 9.1 0 0 4.27 10. I feel as up-to-date on technology as my peers 27.3 45.5 27.3 0 0 4
Cronbach’s Alpha: .873 4.23
SA: Strongly agree, A: Agree, NAD: Neither agree nor disagree, D: Disagree, SD: Strongly disagree
Responses to scale items were coded 1= Strongly disagree, 2= Disagree, 3= Neither agree nor disagree, 4= Agree and 5= Strongly agree [501], [502]. To assess the internal consistency of the Technophilia scale, a test of reliability was conducted and a Cronbach’s alpha value of 0.873 was obtained. This value shows a high level of internal consistency [503], [504].
7.3.2.2. Interaction with the display
Ten participants interacted with the interface over the two-week period. Only one participant reported not checking the display over this period. When asked about the reason preventing him/her from doing so, the participant stated that he/she forgot. This individual did not have to answer the remaining questions of the questionnaire. After analysis of the Technophilia score, it appears that this person had the lowest score of the group. While conclusions cannot be drawn from this fact, it seemed important to mention it. The other
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respondents checked the display several times a week, (50%), once a week (27.3%) and once over the two-week period (18.2%).
7.3.2.3. Design and Content of the interface
The interface is considered very easy (50%) or relatively easy to use (50%) by the respondents. 90% also believe that it is visually engaging. A participant was however confused by the lack of labels on the graph and by the time scale described in the ‘past consumption’ tab; ‘When comparing with the past consumption, we do not know when this past consumption occurred.
Yesterday actually means the last 24 hours and last week means the last seven days. It can be confusing’. Participants’ impressions are described in more details in the table below (see Table
7-6).
Table 7-6. Report of the qualitative data (post-trial questionnaire in office setting)
Regarding the information provided by the display, 54.5% of the respondents consider that the display provides the right amount of information about the building’s water consumption
Items Main findings Illustrative Quotes
Positive aspects
of the interface • Engaging ‘It is engaging and makes it simple to check your real-time water consumption’, ‘it's easy to use with the touch screen’, ‘provides an engagement and monitoring tool’, ‘tips and information are interesting’, ‘it provides tips that are useful to help saving water, ‘good insight on water consumption’. • Ease of use • Tips provided • Information about consumption Negative aspects of the
interface • Lack of units
displayed
‘I would like to be able to differentiate between different types of water usage or room wise’, ‘how much water each activity is using (showers, making a tea…)?’, ‘I couldn’t find the units on some graphs’.
• Provides no disaggregated data
Suggestions for
improvements • Include disaggregation data
‘Having a monthly or weekly average screen with a trend line’, ‘a clear dashboard to see if you are doing well during the current day’, ‘precision on where the water was consumed: is it the toilets, the tap, etc.’.
• Display a
summative period of data
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whereas 36.4% believe that it provides too little information. The overview of the building’s water consumption is the most frequently checked feature for 90% of the participants, followed by the comparisons and social ranking features (10%). Half of the respondents remembered some of the tips and advice provided by the display. This was verified by their responses when they were asked to write down the tips they remembered. These tips include: saving water for the plants, not brushing teeth under the shower, using a glass of water when brushing teeth, using a bowl when washing the dishes, collecting the water when it is heating up and using it for other purposes.
A point-biserial correlation was run to determine the strength of the relationship between the participant’s Technophilia scores and the likelihood of finding the interface easy to use [493]– [495]. Group 1 refers to individuals who consider the interface as a very easy and Group 2 refers to those who consider it as relatively easy to use. Data are mean ± standard deviation, unless otherwise stated. Preliminary analysis showed that there were (a) no outliers in the data, as assessed by inspection of a boxplot for values greater than 1.5 box-lengths from the edge of the box, (b) the Technophilia scores were normally distributed for both Group 1 and Group 2, as assessed by visual inspection of Normal Q-Q Plots and (c) there was homogeneity of variances for the Technophilia scores of Group 1 and Group 2, as assessed by Levene's test for equality of variances (p = .216). There was a small but not statistically significant correlation between the two variables p=.265. Cohens’d (-.2) suggested a small effect size [472].
A Cochran-Armitage test of trend was then used to determine whether there was a linear trend between age and finding the interface easy to use (see Table 7-7)[490], [491]. The null hypothesis tested was ‘HO: There is no linear trend in binomial proportions across age categories’. The age
categories included were 20-25 (n=6), 26-35 (n=2), 36-45 (n=2), over 46 (n=1), and the proportions of respondents who reported finding the display very easy to use was .5, .1, 0, 0 respectively. The Cochran-Armitage test of trend did not show any statistically significant linear trend between the two variables. p = .136. Therefore, we accept the null hypothesis stating that ‘there is no linear trend in binomial proportions across age categories’. Yet, the odds ratio of finding the interface relatively easy to use is 0.5 in age 20 to 25 versus age 36 to over (95% CI = 0.225 to 1.113) and 0.5 in age 20 to 25 versus age 26 to 35 is 0.5 (95% CI = 0.225 to 1.113). This suggests that younger individuals are twice less likely to find the interface easy to use.
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Table 7-7. Summary of the statistical analysis for the ‘demographics’ variables.
Variables Test Sig. Pearson
Correlation
Technophilia scores/Finding the interface easy
to use Point-biserial correlation .216 .390
Age/ Finding the interface easy to use Cochran-Armitage
test of trend .136 N/A
7.3.2.4. Impact of the interface
All participants consider that the interface increased their awareness of the building’s water consumption, either slightly (18.2%), moderately (54.5%) or a lot (18.2%). Regarding their awareness of water issues, one respondent report that his/her awareness did not increase with the use of the interface. The rest consider that it did increase slightly (54.5%) or moderately (27.3%). Likewise, using the interface slightly (54.5%) or moderately (18.2%) increased their awareness of environmental issues. Additionally, the participants overall report that the interface gave them enough guidance to reduce their water consumption at home and at the office (81.8%). Most of them consider that using the display could encourage them to save water in both the long and short term (72.7%). 90.9% would use this kind of device at home and 45.5% would invest in it for their personal use.