3. Survey design issues

One of the main issues in the specification of an ICLV model consists of the observation and the measurement of the attitudes/concerns/perceptions. The survey design is a crucial part since it should allow to characterize the respondents, to come up with respondents' attitudes/concerns/perceptions and to measure them.

Latent variables may be classified as attitudes [20, 21], perceptions [22] and

Approaches for Modelling User's Acceptance of Innovative Transportation…

• Attitudes refer to the users' characteristics and to their approach in real-life society and can be related to the alternatives (alternative-related attitudes) or not (non-alternative-related attitudes). They can be collected through direct or indirect questioning, but indirect questioning seems the most appropriate

• Perceptions are usually interpreted as alternative-related and refer to the users' interpretation and reaction to a stimulus [21]. They can be gathered through

• Concerns may be related to a specific problem/issue. They may depend on the choice context (e.g. the concern towards the environment may depend on the specific problem/activity carried out). They can be collected through direct

Within the aforementioned conceptual framework, it is suggested to design a direct questioning survey considering two different types of questions to be submitted to the respondents: direct and indirect questions. An overview of two exam-

A first example refers to the HySolarKit [26] case study. The questionnaire described in this section was designed [24] to investigate the role of latent factors in the choice of a new automotive technology which aims to electrify/hybridize existing vehicles through an aftermarket kit which can be recharged by the grid but also by solar power (the HySolarKit). The experiment was applied to the case study of the Salerno municipality which is the capital city of Salerno province (region of

The first section of the questionnaire aimed to collect users'socioeconomic, activity-related attributes and household-vehicle characteristic information; there-

In particular, direct questions were about fuel consumption, vehicle reliability, vehicle design and the environmental impact; indirect questions were about three main latent behaviors: the fuel consumption, the vehicle design and the environ-

The questionnaire was completed through a second section based on installation cost scenarios. In particular, each respondent was faced with two scenarios based on

Respondents were provided with a brief description of the technology and its main characteristics: how it works, how it is installed, the different performances (e.g. power, acceleration, speed), the environmental and fuel consumption benefits that can be achieved and the operating time. A brief overview is displayed in more

The second example was about electric vehicle (EV) market penetration [28]. The questionnaire was designed with the aim to investigate the different attributes/ determinants that may influence the decision to purchase an electric vehicle.

fore, respondents were provided with direct and indirect questions.

mental impact. A detailed description is displayed in Tables 1 and 2.

different installation costs (ranging from 500 to 4000 €).

3.2 Example 2: the electric vehicle case study

concerns [23]:

approach [24, 25].

questioning only.

Campania, southern Italy).

detail in Table 3 [27].

21

direct questioning only.

DOI: http://dx.doi.org/10.5772/intechopen.87088

ples of survey design is provided in the following.

3.1 Example 1: the HySolarKit case study

Usually, a survey is structured in different subsections aiming to collect various information from the respondents. First, (a) socioeconomic and (b) household characteristics have to be inquired; then specific sections aimed to capture users' attitudes, concerns and perceptions should be specifically designed, for instance, (c) the users' attitudes and concerns that may influence the willingness to adopt/ use/purchase a new technology and (d) the users' perceptions with regard to the advantages and disadvantages of the technology under investigation. Finally, it is necessary to collect (e) the users' propensity to adopt/use/purchase a new technology. In this case, different scenarios (usually not real but realistic) should be carefully designed in order to cover the possible range of the involved decisional variables.

Even though the literature is consolidated on survey design with respect to Sections (a), (b) and (e), Sections (c) and (d) need to be specifically discussed.

As introduced before, one of the main issues related to the specification and estimation of an HCM relies on how to collect users' attitudes (to observe and quantify them). Since attitudes are entities constructed to represent certain underlying response tendencies, they cannot be measured directly, but they could be inferred by studying behaviour which, in turn, might be reasonably assumed to indicate the attitudes themselves.

The behaviour may be one that occurs in a natural setting or in a simulated situation. In general, different approaches to measure attitudes may be pursued:


This method has two approaches to question the individuals: direct question on the investigated attitude (e.g. how important is the environment) and indirect question (e.g. do you normally buy…).

In general, direct questioning is the most pursued approach since it allows to control the investigated context and requires smaller times and costs. The method application requires the scale of measurement definition. Although the literature has proposed different scales as Thurstone, Likert and Bogardus, the Likert scale [19] has the most flexible, robust and easy to implement scale of measurement.

Approaches for Modelling User's Acceptance of Innovative Transportation… DOI: http://dx.doi.org/10.5772/intechopen.87088

Latent variables may be classified as attitudes [20, 21], perceptions [22] and concerns [23]:


Within the aforementioned conceptual framework, it is suggested to design a direct questioning survey considering two different types of questions to be submitted to the respondents: direct and indirect questions. An overview of two examples of survey design is provided in the following.

#### 3.1 Example 1: the HySolarKit case study

A first example refers to the HySolarKit [26] case study. The questionnaire described in this section was designed [24] to investigate the role of latent factors in the choice of a new automotive technology which aims to electrify/hybridize existing vehicles through an aftermarket kit which can be recharged by the grid but also by solar power (the HySolarKit). The experiment was applied to the case study of the Salerno municipality which is the capital city of Salerno province (region of Campania, southern Italy).

The first section of the questionnaire aimed to collect users'socioeconomic, activity-related attributes and household-vehicle characteristic information; therefore, respondents were provided with direct and indirect questions.

In particular, direct questions were about fuel consumption, vehicle reliability, vehicle design and the environmental impact; indirect questions were about three main latent behaviors: the fuel consumption, the vehicle design and the environmental impact. A detailed description is displayed in Tables 1 and 2.

The questionnaire was completed through a second section based on installation cost scenarios. In particular, each respondent was faced with two scenarios based on different installation costs (ranging from 500 to 4000 €).

Respondents were provided with a brief description of the technology and its main characteristics: how it works, how it is installed, the different performances (e.g. power, acceleration, speed), the environmental and fuel consumption benefits that can be achieved and the operating time. A brief overview is displayed in more detail in Table 3 [27].

#### 3.2 Example 2: the electric vehicle case study

The second example was about electric vehicle (EV) market penetration [28]. The questionnaire was designed with the aim to investigate the different attributes/ determinants that may influence the decision to purchase an electric vehicle.

3. Survey design issues

Transportation Systems Analysis and Assessment

variables.

indicate the attitudes themselves.

One of the main issues in the specification of an ICLV model consists of the observation and the measurement of the attitudes/concerns/perceptions. The survey design is a crucial part since it should allow to characterize the respondents, to come up with respondents' attitudes/concerns/perceptions and to measure them. Usually, a survey is structured in different subsections aiming to collect various

information from the respondents. First, (a) socioeconomic and (b) household characteristics have to be inquired; then specific sections aimed to capture users' attitudes, concerns and perceptions should be specifically designed, for instance, (c) the users' attitudes and concerns that may influence the willingness to adopt/ use/purchase a new technology and (d) the users' perceptions with regard to the advantages and disadvantages of the technology under investigation. Finally, it is necessary to collect (e) the users' propensity to adopt/use/purchase a new technology. In this case, different scenarios (usually not real but realistic) should be carefully designed in order to cover the possible range of the involved decisional

Even though the literature is consolidated on survey design with respect to Sections (a), (b) and (e), Sections (c) and (d) need to be specifically discussed. As introduced before, one of the main issues related to the specification and estimation of an HCM relies on how to collect users' attitudes (to observe and quantify them). Since attitudes are entities constructed to represent certain underlying response tendencies, they cannot be measured directly, but they could be inferred by studying behaviour which, in turn, might be reasonably assumed to

The behaviour may be one that occurs in a natural setting or in a simulated situation. In general, different approaches to measure attitudes may be pursued:

behaviour of people or directly asking to state their feelings regarding the issue being studied. If the aim of the study requires the collection of information from a large number of individuals, this approach is not very practical. Moreover, the observation of peoples' behaviour may reveal the direction of the underlying attitude (i.e. whether it is positive or negative), but it cannot as easily indicate the magnitude or strength of the attitude itself, even when the

• Direct questioning: this approach consists of asking to a set of individuals what their feelings are, as a self-report technique. It serves only for a limited purpose of classifying respondents as favorable, unfavorable or indifferent towards a psychological object. An underlying issue with this technique is the fact that the individuals may possess certain attitudes and behave accordingly to them but may not be consciously aware of them, providing involuntary false

This method has two approaches to question the individuals: direct question on

In general, direct questioning is the most pursued approach since it allows to control the investigated context and requires smaller times and costs. The method application requires the scale of measurement definition. Although the literature has proposed different scales as Thurstone, Likert and Bogardus, the Likert scale [19] has the most flexible, robust and easy to implement scale of measurement.

the investigated attitude (e.g. how important is the environment) and indirect

• Direct observation: this approach is based on either observing the actual

behaviour is the outcome of the attitude being studied.

statements to the direct questionings.

question (e.g. do you normally buy…).

20


#### Table 1.

Psychological statements—Direct questions.


#### Table 2.

Psychological statements—Indirect questions.

The first section of the questionnaire aims to gather information about the users' socioeconomic characteristics, the characteristics of the owned household vehicles and the psychometric indicators of the latent variables. Particularly, two types of

attitudes and two types of perceptions were inquired. The investigated attitudes were towards the environment and about the vehicle's technical features, while the investigated perceptions referred to the advantages and disadvantages of electric vehicles that may affect users' willingness to purchase them. To this end, several direct/ indirect questions were specifically designed adopting a five-point Likert scale (ranging from strongly disagree to strongly agree). The psychological statements used as

• Additional control system that interacts with existing vehicle components and optimizes energy

• A regular electric power outlet, when the vehicle is connected to the grid power in plug-in mode

ICEV ICEV + HSK

A A(25%) A

A mild parallel hybrid structure is obtained by substituting/integrating the rear wheels with in-wheel motors. In this way, the vehicle can operate in pure electric mode (when ICEV is switched off or disconnected by the front wheels) or in hybrid mode (when the ICEV drives the front wheels and the

Your owned car with the HSK

The second section of the questionnaire contains the users' choice behaviour in buying a new car. To this end, a Renault Zoe as the electric alternative and a diesel-

indicators of those unobservable latent variables are detailed in Table 4.

fuelled Renault Clio are considered as conventional vehicles (CV).

Your owned car

(internal combustion engine, ICEV)

DOI: http://dx.doi.org/10.5772/intechopen.87088

Brief description of the HSK

flows

100 km/h)

Table 3.

23

• In-wheel electric engine • Auxiliary lithium-ion battery pack

The battery can be recharged by:

Technological features (averages)\*

Acceleration (acceleration time from 0 to

Overview of the two alternatives in the choice context.

• Photovoltaic panels

The hybridizing equipment (see figure above) consists of:

• Flexible photovoltaic panels installed on vehicle roof and hood

Approaches for Modelling User's Acceptance of Innovative Transportation…

rear in-wheel motors operate in traction mode or in generation mode)

Power P P + (30%) P

Consumptions C C(20%) C Emissions E E(20%) E Operating time T T or 15 m in pure electric mode

Speedmax V V or 40 km/h in pure electric mode

• Rear wheels, when operating in generation mode

Your owned car (internal combustion engine, ICEV) Your owned car with the HSK

#### Brief description of the HSK

The hybridizing equipment (see figure above) consists of:


A mild parallel hybrid structure is obtained by substituting/integrating the rear wheels with in-wheel motors. In this way, the vehicle can operate in pure electric mode (when ICEV is switched off or disconnected by the front wheels) or in hybrid mode (when the ICEV drives the front wheels and the rear in-wheel motors operate in traction mode or in generation mode)

	- Rear wheels, when operating in generation mode
	- Photovoltaic panels
	- A regular electric power outlet, when the vehicle is connected to the grid power in plug-in mode


Table 3.

Overview of the two alternatives in the choice context.

attitudes and two types of perceptions were inquired. The investigated attitudes were towards the environment and about the vehicle's technical features, while the investigated perceptions referred to the advantages and disadvantages of electric vehicles that may affect users' willingness to purchase them. To this end, several direct/ indirect questions were specifically designed adopting a five-point Likert scale (ranging from strongly disagree to strongly agree). The psychological statements used as indicators of those unobservable latent variables are detailed in Table 4.

The second section of the questionnaire contains the users' choice behaviour in buying a new car. To this end, a Renault Zoe as the electric alternative and a dieselfuelled Renault Clio are considered as conventional vehicles (CV).

The first section of the questionnaire aims to gather information about the users' socioeconomic characteristics, the characteristics of the owned household vehicles and the psychometric indicators of the latent variables. Particularly, two types of

Q cons The vehicle fuel consumption significantly influences my choice in purchasing a new car Q rel The vehicle reliability significantly influences my choice in purchasing a new car Q design The vehicle design significantly influences my choice in purchasing a new car Q env The evaluation of the environmental impact significantly influences my choice in

Icons1 The consumption and the energy class significantly influence my choice in purchasing an

Icons 6 When driving I am not willing to behave to reduce the environmental impacts (my driving

Idesign3 When furnishing I am willing to buy pieces with modern design features and original

Ienv3 I really enjoy spending my free time in parks and green areas to breathe clean area Ienv4 How much do you agree with following sentence: We must act and make decisions to

Ienv5 How much do you agree with following sentence: The government should invest in low

Ienv6 I am not willing to use the car during weekend to protect the environment and then reduce

Idesign5 I am willing to install not standard equipment (such as antitheft block shaft) on my own car

Q price The price significantly influences my choice in purchasing a new car

Icons 2 I am usually attentive to the special offers of electric operators

Icons 4 I usually evaluate the car efficiency with respect to the car cost mileage Icons 5 I normally compare the fuel prices among different petrol stations

Idesign1 When parking I am usually careful to avoid having my car damaged

Idesign4 I am willing to go to the body shop mechanic not only for major damages

Ienv1 I often control the exhaust/emission system of my car Ienv2 In consciously make the separate waste collection

reduce emissions of greenhouse gases

Indicator Statement

Table 1.

purchasing a new car

Transportation Systems Analysis and Assessment

Psychological statements—Direct questions.

Attitude towards fuel consumption

appliance

Attitude towards vehicle design Indicator Statement

details

Indicator Statement

Idesign2 I often read journals of design

Attitude towards environmental impacts

energy impact

air pollution

Psychological statements—Indirect questions.

Table 2.

22

Icons 3 My home bulbs are energy efficient

behaviour is normally aggressive)

Indicator Statement


#### Table 4.

Psychological statements of the survey.

These two alternatives were compared in terms of their technical features and then hypothesized that the interviewee has a budget enough to buy a new car to be used in urban areas. The monthly cost of buying and fuelling the conventional vehicle is calculated, considering 8-year monthly payments to buy it and an estimated fuel cost to drive it for 10,000 km per year. This results in a total cost of 192 € per month (Table 5).

and investigated attitudes/perceptions/concerns. Therefore, results from preliminary analyses may give important insights on the survey robustness and a useful guidance for the model specification. In general, the analyses may be divided in basic preliminary analyses based on the analysis of Cronbach's alpha which focuses on the evaluation of the internal consistency of the answers and the evaluation of mean and standard deviations and other advanced analysis, as the factor analysis which aims to identify the latent variables. A further and more detailed explanation

Technical features (averages)\*

Power 92 CV 75 CV Top speed 135 km/h 168 km/h

Consumption 10.9 km/kWh 30.3 km/l CO2 emissions 0 g/km 85 g/km Range 240 km 1364 km

Vehicle B—Diesel Renault Clio 1.5 dCi Life

Electric Gasoline

13.4 s 14.3 s

The Cronbach's alpha, α (or coefficient alpha), is a measure of the internal consistency (or reliability) of the responses to multiple questions that are meant to measure a specific latent variable in a survey using a Likert scale. This indicator aims to tell whether the survey was accurately designed, and the questions were not

For each latent variable, it is necessary to have at least two indirect questions. The higher the number of questions, the better the latent variable would be measured. These questions, if possible, should be a mix of "+keyed" and "-keyed", depending if each one is positively correlated to the latent variable or negatively

When a survey intends to measure more than one latent variable, it is recommended to alternate their questions. This strategy combined to the mix of "+ keyed" and " keyed" is employed in order to encourage respondents to be more aware of each item and the response provided and, therefore, increases the probability of gathering valid responding. If not, respondents may realize which latent

of the methods is provided below.

Comparison of the two alternatives in the choice context.

Vehicle A—Electric Renault ZOE Life R90

DOI: http://dx.doi.org/10.5772/intechopen.87088

Approaches for Modelling User's Acceptance of Innovative Transportation…

4.1 Cronbach's alpha

Acceleration (0–100 km/h)

Table 5.

answered randomly.

(Table 6).

25

After the comparison, each respondent was faced with five monthly cost scenario setup for the electric vehicle. They started from the same value calculated for the diesel vehicle (i.e. 192 €/month), and then it was considered that the EV would have cost 10, 20, 30 and 40% more (€211, €230, €250 and €270 per month, respectively).

#### 4. Preliminary analyses

In the case of HCM, descriptive and statistical analyses of the collected answers regarding the perception indicators are necessary for two main reasons: firstly, they allow supporting the soundness of the experimental design setup; secondly, they allow deriving first correlations between observed behaviour, collected attributes

Approaches for Modelling User's Acceptance of Innovative Transportation… DOI: http://dx.doi.org/10.5772/intechopen.87088


#### Table 5.

These two alternatives were compared in terms of their technical features and then hypothesized that the interviewee has a budget enough to buy a new car to be used in urban areas. The monthly cost of buying and fuelling the conventional vehicle is calculated, considering 8-year monthly payments to buy it and an estimated fuel cost to drive it for 10,000 km per year. This results in a total cost of 192 €

DISinfr When driving an EV, I would always be worried about the lack of charging points

DISred\_fea Compared to a normal car, EV are inferior in terms of performances

F\_cons The vehicle fuel consumption significantly influences my choice in purchasing a new

F\_tech\_fea The vehicle technical features significantly influence my choice in purchasing a new car

TF\_top\_speed When I am choosing a car, I find myself spending a lot of time checking out differences

TF\_range The vehicle range is very significant with respect to my mobility needs in everyday life

F\_poll I care about the amount of pollution generated by a car when it's being used

After the comparison, each respondent was faced with five monthly cost scenario setup for the electric vehicle. They started from the same value calculated for the diesel vehicle (i.e. 192 €/month), and then it was considered that the EV would have cost 10, 20, 30 and 40% more (€211, €230, €250 and €270 per month,

In the case of HCM, descriptive and statistical analyses of the collected answers regarding the perception indicators are necessary for two main reasons: firstly, they allow supporting the soundness of the experimental design setup; secondly, they allow deriving first correlations between observed behaviour, collected attributes

per month (Table 5).

Attitudes towards the environment

Transportation Systems Analysis and Assessment

car

Attitudes about technical features Indicator Statement

Advantages

Disadvantages

Table 4.

Indicator Statement

Indicator Statement

Psychological statements of the survey.

TF\_power I prefer driving a car with a powerful engine

in terms of top speed (km/h)

ADLess\_parts I prefer having a car with less moving parts

DISbatt\_range The low range of the battery is a real disadvantage

TF\_accel The immediate acceleration increases my driving pleasure

ADRed\_CO2 I am interested in EV to contribute to the emissions reduction

ADEfficiency Compared to a normal car, EV are superior in terms of energy efficiency ADRed\_poll I believe using EV can significantly reduce the acoustic pollution in cities

Indicator Statement

4. Preliminary analyses

respectively).

24

Comparison of the two alternatives in the choice context.

and investigated attitudes/perceptions/concerns. Therefore, results from preliminary analyses may give important insights on the survey robustness and a useful guidance for the model specification. In general, the analyses may be divided in basic preliminary analyses based on the analysis of Cronbach's alpha which focuses on the evaluation of the internal consistency of the answers and the evaluation of mean and standard deviations and other advanced analysis, as the factor analysis which aims to identify the latent variables. A further and more detailed explanation of the methods is provided below.
