Vol. 2: Work-in-progress papers f|ift 203

REFERENCES WITHIN THE CONTEXT OF CUSTOMER VALUATION

Cornelsen, Jens University of Erlangen-Nuremberg

Diller, Hermann 1 University of Erlangen-Nuremberg

ABSTRACTThe increasing individualization of customers' requirements and behaviors leads to an increasing diversity of customers' economical potentials. From the supplier's point of view, the necessity increases to calculate individual customer values. The Customer Value reflects the economical overall worth of customers by acquiring all direct and indirect contributions of the customer that allow an offering company to reach its targets. The Reference Value (,,RV") is considered to be one of these indirect contributions. It can be directly attributed to the oral recommendation behavior of actual customers. Corresponding to our RV-model, the reference value is determined especially by number, intensity and tonality of the references. Within the frame of an empirical study we could ascertain that the reference value of car owners - related to one average purchase cycle - lay between -3.320,- US$ and +11.150,- US$.

1 Co-author: Prof. Dr. Hermann Diller, University of Erlangen-Nuremberg, Department of Marketing, Lange Gasse 20, D-90403-Nuremberg/ Germany (Phone #49/ 911/ 5302- 214, Fax #49/911/5302-210, E-mail: wsma01@wsrz2.wiso.uni-erlangen.de).

204 T|p. 14"1 IMP Annual Conference

1. CUSTOMER VALUATION IN RELATIONSHIP MARKETING

Already in the eighties, Peters/ Waterman (1982) found that "closeness to

the customer" is one of the most fundamental determinants for a company's

long-term success. In the meantime, "closeness to the customer" (e.g.,

Homburg 1995) is in the focus of nearly all considerations in relationship

marketing 1 . Such considerations, however, often lead to an effort for ,,zero

defections" (e.g., Reichheld/ Sasser 1990), i.e. to the trial to maintain all(!)

relationships and thus to reach a customer fluctuation of ,,zero". Instead,

the point is first of all to focus on the satisfaction of those customers that

are valuable from the supplier's point of view. Only these customer are

important for the supplier and thus it is important to tie them to the

company. Moreover, customers want to be ,,served" more and more

individually. In the past, it was possible to satisfy great customer groups

with more or less standardized offers, whereas today products and services

must be more and more individual and have to be "designed" specific for

nearly each customer. The increasing heterogeneity of the customer

requests is directly connected with an increase of the company's

complexity as can be widely observed. Especially with respect to the

background of limited marketing and sales budgets it is imperative to

consider that the increasing part of individual services raises customer-

specific costs, e.g. costs for special packages, product modifications, etc.

Consequently, the application of marketing and sales instruments may not

only be seen exclusively from the point of view of customer satisfaction,

customer bonding and increasing sales, but must also be seen in their

1 In this context we want to follow the (extensive) term definition of Parvatiyar/ Sheth (1994, p. 1) who interpret relationship marketing as orientation within the marketing ,,that seeks to develop land maintain; remark of the author] close interactions with selected customers, suppliers (...) for value creation through cooperative and collaborative efforts. Especially regarding the calculation and use of reference values, such a ,,network prospective" seems to be appropriate.

Vol. 2: Work-in-progress papers ri 205

effects on profitability and ultimately from the point of view of the

customer value.

2. CUSTOMER VALUE: DEFINITION AND DETERMINANTS

The customer value - from the supplier's point of view is a specific

measure for the future economical "worth" of customers, i.e. their direct

and indirect contribution to reach the goals of a supplier. In negative

words, the customer value comprises all monetary and non-monetary losses

that arise when a certain customer finishes the relationship. In that case, the

supplier "loses" not only the economical potential of customers that can be

realized directly, as the sales or profit potential, but also pre-economical

potentials (figure 1):

"direct"

customer profitability

customer revenues

customer sales

customer bonding

CUSTOMER VALUE

"indirect"

references

cross-selling

information

profitability-based

FIGURE 1: Determinants of the customer value

sales-based

206 IIP 14* IMP Annual Conference

For example, the cross-selling potential (e.g., Kamakura et al. 1991) of

a customer is a measure indicating if and to what extent an existing

relationship can be expanded onto further products or product groups of the

supplier. Such expansions into other product groups broaden the

(economical) basis for relationships and can therefore be also interpreted as

part of the customers' economical potential.

In opposition to that, the information potential (e.g., Reichheld 1996)

of a customer results from the total of innovative and usable information

that the supplier receives from the customer and that can be used

correspondingly by the company for improving product quality or for

optimizing procedures in purchase, production, and marketing. We would

like to quote in particular suggestions, complaints and proposals for

products or processes. They may lead to more efficiency or/ and to cost

reductions in production, logistics, but also in the marketing / sales field or

in the accounting. In this respect, they represent economical potentials that

should be considered within the calculation of customer values. This

becomes very clear when lead users are concerned whose experiences in

dealing with new products become part of product developments and

product improvements.

Last but not least, it is the individual reference potential that also gets

lost with a non-loyal customer. Similar to recommendations, references

present a form of direct, verbal communication between several persons

where concrete information about a supplier or his products/ services are

interchanged. References are a customer-specific economical potential

because they enable a supplier to indirectly receive higher ,,sales" and at

best to reach also an improved profitability. The resulting reference value

can be attributed originally to the reference giver. This leads to a

completely new overall understanding of customers exceeding the mere

customer classification, e.g. with respect to an optimum resource allocation

Vol. 2: Work-in-progress papers f||E 207

for direct advertisements or for the distribution. The former partial

view of a customer is now replaced by a total view.

Apart from these direct and indirect economical potentials of customers

that ultimately determine the short-term customer value, the long-term

customer value (,,customer lifetime value") depends in addition on the

expected duration of the relationship (e.g., Dwyer et al. 1987; Dwyer 1989;

Reichheld/ Sasser 1990; Ganesan 1994). As the duration of a business

relationship is not known in advance and can be prognosticated only under

great uncertainty, we use ,,customer bonding" (e.g., Dick/ Basu 1994;

Diller 1996; Bendapury/ Berry 1997) as indicator for the ,,stability" of a

relationship.

For defining customer bonding we lean on Dick/ Basu (1994) who

define customer bonding or customer loyalty, respectively, ,,as the strength

of the relationship between an individual's relative attitude and repeat

patronage". Accordingly, different degrees of customer bonding result from

the combination of cognitive, affective and conative antecedents. The

stronger the resulting bonding, the smaller is c.p. the likelihood that a

customer changes to one of the competitors. As inverse, customer bonding

thus relatives" the customer-specific economical potential variables

determined before (figure I).

Depending on the economical ,,base", completely different systems of

customer valuation can be distinguished. If one intends to determine

,,sales-based customer values", all customer-based pre-economical

potentials (i.e. reference potential, cross selling potential and information

potential) have to be monetarized with respect to their sales effect. On the

other hand, if the customer profitability is selected as economical base, all

cost effects that can originally be attributed to corresponding customer-

related reference activities, cross selling activities and information

activities are to be included into the calculation of ,,profltability-based

customer values" apart from the mentioned sales effects. It can be easily

208 I|JP 14th IMP Annual Conference

understood that the total of the customer values calculated in such a way

does not correspond to the company-related overall value. In this respect,

customer value analyses are sensible only on a desegregated, customer- or

customer group-related level!

In the following section we would like to go into the details of the

reference value as an important determinant of the customer value. For this

purpose, first the term references" will be clarified before a separate

model of the reference value (RV-model) will be presented.

3. AN INTEGRATED CONCEPTUAL FRAMEWORK OF THE REFERENCE VALUE

3.1 Definition and delimitation of references

Originally, the term ,,references" proceeds from the capital goods industry

where so-called reference machines - potential customers can inquire the

efficiency of a certain machine - are used directly for giving ,,evidence" of

the technical competence of a supplier. Also consultant firms, hotel trade

companies or manufacturers of rarely installed utility goods frequently use

references as sales argument in order to document entrepreneurial

efficiency and trustworthiness. Similar effects can also be expected if

private or commercial customers make positive or negative experiences

with new suppliers or offers, and pass them on to their social environment.

It has been known for years that such interpersonal communication

processes have a great influence onto purchase decisions of private and

commercial buyers (e.g., Arndt 1967; Yale/Gilly 1995; Bone 1995).

In both cases, references produce an (indirect) advertising effect for the

concerned supplier. In times of an omnipresent information overload", this

effect can be seen as a supplement or a substitute for mass media

communication. In the following, we want to concentrate mainly on oral,

interpersonal communication procedures and define references as follows

(e.g., Cornelsen/ Schober 1997):

Vol. 2: Work-in-progress papers %R 209

O Direct,

© private,

© oral,

O positive, negative, neutral

© communication between two or more persons

© about a supplier or his products.

As personal information exchange between two or more persons, a

reference is a direct, interpersonal communication that connects the

individual customer to the people of his social environment. A separation

of indirect communication forms, as e.g. testimonial advertisement, is

connected with this focus. Related to the persons taking part in the

communication process, a reference is first of all a private communication

not motivated by commercial reasons that is regarded for that reason as

highly trustful. This does not exclude, though, that expressing private

opinions may produce commercial effects what is then exploited by the

suppliers, as e.g. within the frame of "member-get-member" campaigns for

journal subscriptions. With the limitation onto oral communication, all

effects are excluded from consideration that can be traced back to non­

verbal communication procedures. Non-verbal ,,charisma" of certain

persons, that often leads to an imitative consumer behavior, is dismissed

out of practicability reasons. As an example, we would like to mention the

imitative behavior of mobile telephone users which could widely be

observed in the early 90ies. Related to the communication "tonality",

references comprise negative, neutral as well as positive remarks about a

supplier and his products. That is to say that references differ from

recommendations that show an exclusively ,,positive" tendency according

to our definition of reference.

210 IMP 14* IMP Annual Conference

3.2 ,,RV-Model": Model of the reference value

Proceeding from above considerations we developed our ,,RV-"model with

which we attempt to calculate and explain the determinants of the reference

value from the supplier's point of view. The reference value includes all

monetary effects caused by the reference potential that is different for each

individual customer. The reference value expresses itself ultimately in the

proportional, individual customer value of the corresponding reference

recipients which has to be assigned originally to the customer giving the

reference, apart from his own customer value. Analog to the customer

value model, sales- and profitability-related systems are to be

differentiated.

As Figure 2 makes clear, our reference value results from the

reference rate on the one hand, and from the individual reference

potential on the other hand: The reference rate reflects the "calculative"

part of the average purchasing volume of an industry due to product-

related, personal conversations and not due to other activities providing

information, as e.g., catalogues, sales talks, etc. It is not calculated

individually for each reference recipient. The reference rate results from

corresponding valuations concerning the average annual purchase volume

within an industry as well as the average, percental influence of references

onto the final purchase decision.

Vol. 2: Work-in-progress papers 211

social network

opinion leadership

I

customer satisfaction

r i ^

j& reference rate

"quantity" "intensity" "tonality"

reference potential

REFERENCE VALUE (RV)

FIGURE 2: ,,RV-Model": Model of the reference value

In opposition to this, the customer-specific reference potential

comprises all potential customers that an existing customer is able to reach

within his or her social network with positive, negative or neutral

information. In this respect, the actual customer can be seen as a supplier's

sales person. Consequently, the reference potential is determined in

particular by the number of people and the frequency of conversations

within the social network ("quantity" of references), the customer

satisfaction ("tonality") as well as the opinion leadership ("intensity")

as can be seen in figure 2.

212 IMP 14* IMP Annual Conference

3.2.1 Opinion leadership

Related to the reference potential, we define opinion leaders as persons

who exert a strong influence on other's attitudes, opinions and ways of

overt behavior within the frame of interpersonal communication. By

exercising influence onto other persons, opinion leaders influence the

intensity" of references, the reference potential and in the end the

reference value.

When looking at the ,,classical" models of opinion leadership (e.g.,

Lazarsfeld et al. 1948; Katz/ Lazarsfeld 1955), a relatively ,,static"

differentiation between active opinion leaders on the one hand and passive

opinion followers on the other hand was supported at that time. Not least

based on the symmetrical models of the opinion leadership (e.g., Troldahl/

van Dam 1965) it is assumed today that opinion leadership cannot be

occasioned by certain characteristics of a person but has to be seen as take­

over of situative communication roles. Finally, this corresponds to the idea

of ,,monomorph" opinion leaderships that refer to one or only a few

product areas (e.g., Katz/ Lazarsfeld 1955). According to this theory, an

opinion leader for cars does not automatically exercise his influence in the

areas ,,hi-fi" or ,,cosmetics".

The dichotomy in ,,opinion leader" and ,,non-opinion leader", however,

already seems to be problematic. In reality, the idea of gradual opinion

leaderships has to be assumed. The degree of opinion leadership would

then be a relative measure for indicating to which extent an individual

influences his social environment (,,intensity"). In principle, such an

influencing is based on two different factors according to Briine (1989):

3 product-dependent factors (,,expertise")

3 product-independent factors (,,personality")

On the one hand, the point is that a customer has a long-term interest in

the concerned product area, e.g. cars, and thus as an expert (e.g., Alba/

Hutchinson 1987; Mitchell/ Darkin 1996) knows a lot about cars

Vol. 2: Work-in-progress papers l|fp 213

(,,expertise"). His product- or market competence has the effect that

other persons of the social environment have an increased subject-specific

interest in this customer. If required, e.g. when buying a new car, people

more frequently refer to persons who, according to their opinion, are

competent and credible, as they are e.g. friends or acquaintances. As

experts are consulted more frequently than other persons, ,,expertise" can

be regarded as the first determinant of opinion leadership.

On the other hand, persons or groups of persons also become opinion

leaders because friends and acquaintances orientate themselves by them,

that means independent of the respective product area. Such reference

persons or reference groups (e.g., Bearden/ Etzel 1982; Childers/ Rao

1992) are characterized by a ,,dominating appearance", as e.g. strong

personality, extroversion or social centrality. Friends and acquaintances ask

for their opinions to be given praise or to avoid disapprovals of their

purchases. At the same time the general orientation toward such reference

persons serves to gain a basis for the ,,desired" purchase behavior. The

general personality can thus be seen as the second determinant of opinion

leadership.

When regarding these points simultaneously, the question arises, though,

to which extent the two factors explain the opinion leadership. An

empirical study comprising 175 persons carried out by Briine (1989) in the

product areas ,,Photo", Automobiles" and ,,Fashion" showed in this

context that opinion leadership is characterized to a great extent by

expertise in all the three areas. In addition to that, it could be observed in

the ,,socially influenced" product areas ,,Automobiles" and ,,Fashion" that

opinion leadership is also influenced by ,,personality" to a quite

considerable extent. That means the ,,personality" obviously plays a more

important role the more ,,socially influenced" a product area is.

Related to our RV-model we can state that opinion leadership influences

the ,,intensity" of references. The stronger the degree of the opinion

214 IIP 141* IMP Annual Conference

leadership, the higher the reference efficiency" and thus c.p. the impact of

a reference on the recipient. The reference potential, however, does not

exclusively depend on the ,,depth", though, but also significantly on the

,,width" of references; that is the size of the individual ,,social network".

3.2.2 Social network

Many research areas in marketing theory are inherently concerned with

exchange or interactions between actors in networks (e.g., Bagozzi 1975;

Solomon et al. 1985; Anderson et al. 1994). A social network ,,is a

composite of a larger number of actors and the pattern of relationships that

ties them together" (lacobucci/ Hopkins 1992).

The ,,actors" represent the structural elements of social networks, that

means all persons in the social environment of the examined customer for

whom an individual reference value is to be calculated: First of all, the

members of the family, the friends and acquaintances as well as the

colleagues and club mates with whom regular conversations take place

belong to this circle. From the methodical point of view, this agrees with

ego-centralized networks that correspond to the idea of a ,,star-shaped"

framework of relationships. In contrast to the investigation of ,,complete

networks", the direct relations of one person to other persons are in the

center of interest in this case. We would like to assume the idea of ego-

centralized networks when we try to calculate individual reference resp.

customer values.

As a rather proceeding-controlled component of ego-centralized network

analysis, however, the ,,patterns of relationship" primarily aim at the

manner of network-internal contacts and conversations. In this context,

Milardo (1992) differentiates ,,support", ,,political" as well as

information" networks. The three types of networks are characterized by a

small mutual overlapping and can thus be considered to be relatively

autonomous. Basically, the different types of networks can be characterized

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by the ,,quantity" and the ,,tonality" of the conversations: The

,,quantity" of the conversations is produced within the frame of the model

first of all by the number of persons with whom subject-related

conversations, e.g. references, are held. As this is not carried out with the

same intensity (frequency) in each circle, the ,,quantity" is to be adjusted.

According to the strength of social ties, Granovetter (1982) differentiates

,,strong ties" and ,,weak ties". Apart from the ,,quantity" of the reference

conversations, reference value also strongly depends on the ,,tonality" of

such conversations. In our RV-model they are taken into account by means

of the variable ,,customer satisfaction".

3.2.3 Customer satisfaction

Customer satisfaction belongs to the psychical consequences after having

bought a product or having made use of a service. It is one of the results of

post-purchase evaluation. In this evaluation, the customer compares the

expectations regarding the service performances of a company with the

actually made experiences (e.g., Thibaut/ Kelley 1959; Schiitze 1992).

Depending on whether the expectations correspond to the actual

performance or whether they diverge, different reactions of the customer

are caused. Apart from reactions as brand loyalty or fluctuation, complaint

or praise toward the company, these are especially comments of customers

toward third parties, i.e. references.

In this context it has to be emphasized that the ,,motivation" of a

dissatisfied customer normally is much higher than that of a ,,merely"

satisfied customer. Empirical studies prove that a dissatisfied customer

passes on his negative experiences to an average of 10 to 12 persons of his

social environment whereas a satisfied customer passes on his positive

experiences to an average of only 3 persons (e.g., Hansen/ Schoenheit

1987, p. 34). Accordingly, dissatisfaction to a high extent holds the danger

of unwelcome multiplicatory effects. That is why Heskett et al. (1994, p.

216 IIP 14* IMP Annual Conference

144) talk about terrorists", who (...) speak out against a poorly delivered

service at every opportunity!" On the other hand they call satisfied

customers ,,apostles" who ,,carry the positive messages into the world".

Hence, the statement of Engel et al. (1969, p. 15f.) does not seem to be

exaggerated when they establish: ,,Your best salesman is a satisfied

customer!"

With respect to our RV-model we say that in the positive expression the

customer satisfaction exclusively determines the ,,tonality" of a reference.

Dissatisfaction, however, not only influences the ,,tonality" but also the

intensity" of a reference. Furthermore, detailed studies have to be

performed to find out how strong the corresponding influence actually is, at

the moment it can only be suppose it.

After having discussed the most important determinants of the reference

value, that are ,,opinion leadership", ,,social network", satisfaction, we are

now confronted with the problem how to integrate the reference values into

comprehensive models of the customer value.

3.3 The reference value within different customer valuation systems

Related to the methodical integration of reference values into customer

valuation systems, different aggregation steps" can be differentiated:

(1) The methodically simplest solution is to calculate customer scores

based on special scoring models. The valuation of different customer-

related ,,effects", as e.g. cross selling, references etc. (figure 1) is

performed with the help of points or scores. The higher e.g. the reference

score, the more valuable is c.p. the observed customer. Consequently, the

customer value to be determined is no monetary value, but rather a

customer score which can be interpreted only insufficiently. This, however,

is what we wanted to avoid with our integrated framework of customer

value.

Vol. 2: Work-in-progress papers ' 217

(2) From our point of view a monetary customer value model is

more favorable. Within the frame of "one-dimensional" models, the

different direct and indirect economical potentials of the customers (figure

1) are aggregated to a comprehensive, monetary customer value after they

have been transformed. The difficulty of this approach lies less in the

analytical aggregation of the individual ,,sub-values" than rather in the

derivation of its determinants. If we follow a dynamic long-term view

(,,customer lifetime value"), then the customer loyalty is to be included into

the method approach as ,,corrective variable" as well as - corresponding to

the classical capital expenditure anlysis - a discounting interest rate.

(3) Especially regarding the long-term perspective of business

relationships, the value of a customer can be represented also with the help

of multi-dimensional customer value models, i.e. customer portfolio

analyses. The basic idea of a comprehensive investment control of

strategical business units that was taken from the portfolio theory of

Markovitz (1970) is transferred onto the investment object ,,customer".

Whether capital is invested into a customer or not depends on the one hand

on his ,,attractiveness" (external dimension), on the other hand on the

relative position within the competition" of the supplier for the customer

(internal dimension). The customer attractiveness presents the value of the

customer relationship from the supplier's point of view which comprises

the one-dimensional customer value (2). According to this, the monetary,

customer-specific reference value is one of the components of ,,customer

attractiveness".

4. REFERENCES WITHIN THE AUTOMOBILE INDUSTRY: RESULTS OF AN EMPIRICAL STUDY

Regarding our ,,RV-model" introduced in the 3rd chapter it is of particular

interest to clarify in conclusion how to caluculate monetary reference

values for individual customers or customer groups on the basis of the

218 I t\l P 14* IMP Annual Conference

presented model (figure 2): Which customers are the reference kings"

(with high reference value!) and which are the reference losers" (with

small resp. regative reference value!). We therefore performed - together

with a great market research institute - an empirical study. Within the frame

of a non-accidental selection, 200 car owners were interviewed regarding

their reference behavior, i.e. finally regarding the determinants of the

reference value. The final results will be presented in autumn 1998 within

the frame of a publication. Nevertheless, some interesting results can

already be presented:

We found out, for example, that a strong variance in the level of

customer-specific reference values could be seen across all car categories.

Related to a period of 4 years - this corresponds approximately to an

average automobile purchase cycle - customer-specific reference values

between -3,320.- US$ and +11,150.- US$ ( +1.290,- US$) were made

out. Taking into account that an average car buyer spends appr. 20.000,-

US$ for his new car, an average reference quota of 6.5% is produced.

Depending on the car category, this reference quota differs between 5%

and 10%. A customer has to be assigned, apart from his direct sales, with

up to 10% as reference agio" resp. reference disagio". ,,Reference

disagios" refer to such persons for whom negative reference values are

determined. These persons are dissatisfied with their present car brand and

expressed their negative opinion toward relatives, friends, acquaintances

etc.

Furthermore, we could establish that the level of the reference value is

determined particularly by the number of persons with whom the topic

,,cars" is discussed, i.e. finally by the size of the social network

(,,quantity"). Technical employees, for example, who generally have a

higher interest in technical things, talk about cars with an average of 18

persons, whereas commercial clerks talk about cars only with an average of

12 persons. Generally, cars are talked about chiefly with friends and

Vol. 2: Work-in-progress papers rl 219

aquaintances. As figure 3 shows, technical employees, for example,

discuss the subject ,,cars" with 0 6.2 friends or acquaintances, but only

with 0 4.7 colleagues, 0 3.8 members of their families and 0 3.3 club

mates. In this respect, managers are an exception. Their interest in cars is

considerably smaller. When they talk about cars, however, they do it in 3

out of 4 cases with their fellow managers, e.g. when buying a new

company car.

Who talks with whom about cars?

manager

self-employed

technical

commercial

0,0 1,0 2,0 3,0 4,0 5,0 6,0 7,0 8,0

(Number of persons)

FIGURE 3: Conversations about cars

In general, we found out that the profession" has a statistically

significant influence on the number of interlocutors in the respective social

circles. Participants of subject-related conversations are mainly determined

220 t|||t 14th IMP Annual Conference

by the profession of a customer resp. his professional position. Supposing a

car manufacturer is informed about the professions of his customers, then

he knows in which social networks they hold reference conversations.

Therefore, he is able to plan and control customer-related marketing and

sales instruments. He will, for example, try to motivate a manager to

initiate reference conversations about cars mainly with fellow managers as

it is in these circles where managers talk about cars.

Especially regarding limited marketing- and sales budgets it is of

increasing importance to support the best allocation of financial, personal

and informational resources. Permitting an overall view of the customers,

references resp. customer values become one of the possible steps toward a

more rentability-oriented thinking that gains in importance particularly

with respect to the considerations regarding the shareholder value".

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