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Customer Complaints, Defection and Lifetime Value
George Knox and Rutger van Oest*
This Version: July 1, 2010 * George Knox and Rutger van Oest are Assistant Professors of Marketing at Tilburg University, Warandelaan 2, 5000LE Tilburg, The Netherlands, (email) [email protected] (tel) +(31) 13 466 8232 (fax) +(31) 13 466 8354, and (email) [email protected] (tel) +(31) 13 466 2057 (fax) +(31) 13 466 8354. The authors thank Bart Bronnenberg, Marnik Dekimpe, Josh Eliashberg, Els Gijsbrechts, Rik Pieters and participants of the 2007 Tilburg Summer Research Camp, 2007 Marketing Dynamics Conference, 2008 Marketing Science Conference, 2008 Direct/Interactive Marketing Research Summit, the Zaragoza Logistics Center, and 2009 Marketing Science Conference for their detailed and useful comments, and Sander Beckers and Inge Vening for their help recording data.
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Customer Complaints, Defection and Lifetime Value
Abstract
Complaint management is an essential component of defensive marketing; yet the impact
of customer complaints and firm responses to those complaints on subsequent customer
purchasing remains unexplored. Using a unique database that tracks actual purchases,
complaints, and recoveries for 20,000 customers over 2.5 years, we identify eight complaint and
six recovery types and investigate their effects on customer defection and lifetime value (CLV),
while accounting for the customer’s history with the firm. Previous complaints (purchases)
intensify (dampen) the negative impact of current complaints, but the effect of past complaints
fades over time more quickly than that of past purchases. Complaints about out-of-stock items
most often result in defection, while firm responses involving merchandise certificates (i.e., store
credit) often lead to sustained recovery and are more effective (in terms of CLV) than refunds.
Although providing a constructive recovery tends to be financially rewarding, extra
compensation usually does not appear worth the extra resources.
KEY WORDS: Complaints, Complaint Management, Defection, Customer Lifetime Value, Failure, Recovery
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INTRODUCTION
Product and service failures are an unavoidable reality of business and may represent
critical turning points in the customer-firm relationship. Complaints give voice to the resulting
dissatisfaction and offer firms an opportunity to save the customer by choosing an effective
recovery (Fornell and Wernerfelt 1987). Firms can also monitor complaints to anticipate failures
before they escalate (Berry and Parasuraman 1997; Hart, Heskett and Sasser 1990). Previous
studies have examined both recovery effectiveness and failure severity in terms of customer
perceptions and intentions, yet research that uses behavioral and financial outcomes such as
customer retention or lifetime value is still rare (Zhu, Sivakumar and Parasuraman 2004). This
has led to a call from both academics (Parasuraman 2006; Rust and Chung 2006) and managers
(Goodman 2006) to make complaint management more financially accountable.
To that end, we develop and estimate a model that links two important behavioral metrics
– customer defection and lifetime value (CLV) – to an actionable set of complaint and firm
recovery types obtained from company records, while accounting for the customer’s history with
the firm. Since our setting is non-contractual, firms cannot directly observe customer defection;
instead they must infer it from the timing of customer-firm interactions (e.g., Schmittlein,
Morrison and Colombo 1987; Fader, Hardie and Lee 2005). Our data come from a major U.S.
internet and catalog retailer and track purchases and complaints for 20,000 customers over 2.5
years. Such a panel database, that describes actual customer behavior over time, has not yet been
used to study complaint management (Rust and Chung 2006, p. 563).
Although most dissatisfied customers do not complain, complaints can be managerially
useful because they are observed indicators of latent dissatisfaction and potential defection
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(Blattberg, Kim and Neslin 2008). Studying their effects on actual subsequent purchasing offers
several advantages over the more common survey and experimental approaches. First, complaint
records are typically stored in firm data warehouses, and, when combined with transaction data,
can provide a low-cost but meaningful way to trade off competing recovery options on the basis
of financial impact (i.e., CLV). Second, actual complaints represent both extreme and “typical”
incidents (rather than the mostly extreme memory-based responses from surveys), and trigger
“real-life” rather than experimentally-induced reactions (Weiner 2000).
In the next sections, we present the conceptual framework underlying our empirical
analysis, followed by a description of our data set and the model. Next, we discuss the empirical
findings and illustrate the impact of several firm recoveries on CLV. The final section offers the
implications of the findings for information systems, failure prevention and recovery strategies.
CONCEPTUAL FRAMEWORK
CLV and modeling framework
CLV is the sum of all discounted contribution margins over the customer’s lifetime
(Berger and Nasr 1998; Blattberg, Kim and Neslin 2008). Typically, it is computed on a time
period basis (e.g., annual time blocks), with the two drivers being the customer’s lifetime (or
retention) and the contribution margin per period, discounted by the exogenous discount rate
(Kumar and Reinartz 2006). However, similar to Rust, Lemon and Zeithaml (2004), we consider
a non-contractual setting in which the data are defined on an event basis (i.e. purchases and
complaints). Correspondingly, CLV results from (1) potential defection after purchases and
complaints, (2) the timing of these events, and (3) the dollar amount that is spent on each
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purchase occasion (multiplied by the margin rate and discounted by the discount rate). While
Rust, Lemon and Zeithaml (2004) assume that a firm can always have a fraction of a customer’s
business (“always a share”), our model assumes that customer defection is an absorbing state
(“lost for good”), i.e., customers are “active” until they irreversibly “defect”, an assumption
shared by many models of non-contractual relationships (e.g., Fader, Hardie and Lee 2005;
Schmittlein, Morrison and Colombo 1987). As defection is not observed, its likelihood is
unknown and needs to be inferred.
[Figure 1 About Here]
The flow chart in Figure 1 describes the consumer's sequence of steps, with equation
numbers for later reference. Customers start in an “active” state and may purchase or complain
whenever they want to, as long as they stay active. If the event is a purchase, the customer
spends a certain amount and may accompany the purchase by a complaint on the same day (e.g.,
not qualifying for free shipping). Any complaint, either separate from, or on the same day of a
purchase, is of a specific type and triggers a response by the firm. At the end of the event, the
customer decides whether to stay with the firm (and remain in the active state for at least one
more round) or defect (and move to the absorbing inactive state). Though our model contains
several steps, all of these are needed in order to forecast customer behavior into the future and
calculate CLV. Below, we discuss the potential indicators of customer defection, i.e., the specific
complaint types, recovery types and the role of customer history. We do so with the
understanding that underlying dissatisfaction is the final driver of defection: though complaints
are observable indicators of dissatisfaction, they do not cause defection themselves.
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Complaint types
Based on the services and complaint literatures, we identify eight mutually exclusive
complaint types. They are (1) perceived price issues, (2) order placement and billing issues, (3)
out-of-stock, (4) late or no delivery, (5) wrong package contents, (6) wrong information, (7)
defective product, and (8) product-not-as-expected. Table 1 provides the full set of complaint
types along with their frequency of occurrence in our data, the dimensions along which they
differ, and their expected effects on defection. Complaint type 1 is the perceived price attribute
in the e-service quality framework of Zeithaml, Parasuraman and Malhotra (2000) and includes
issues such as expired promotional offers or not qualifying for free shipping. Complaint types
(2)-(6) are the attributes captured in the reliability/fulfillment dimension of these authors.
Complaint types (7)-(8) are taken from Kelley, Hoffman and Davis (1993). They go beyond e-
service quality and are product-related. The three super-categories, i.e. price, fulfillment and
product, are provided in the second column of Table 1.
[Table 1 About Here]
The services marketing literature has identified several dimensions along which failures
and subsequent complaints can be classified in our context. An outcome failure refers to what a
customer has received – the core service – whereas a process failure concerns how the service is
received (Smith, Bolton and Wagner 1999). Recall-based surveys indicate that incidents related
to the outcome are more negatively experienced than incidents related to the process (Bitner,
Booms and Tetreault 1990), and are more often mentioned as a reason for abandoning the firm
(Keaveney 1995). Perceived prices issues (type 1) and order placement and billing issues (type
2) are related to the process; hence their predicted effects on defection are modest. Wrong
information failures (type 6) involve customers blaming the firm for having informed them
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incorrectly (for example about product size or color) and therefore may contain both process and
outcome elements. The other five failure types are related to the outcome, as shown in Table 1.
Attribution theory suggests characterization of failures by their underlying causes as
inferred by the complainant. The causal dimensions are locus, controllability and stability
(Weiner 1980). Customers react more negatively if the failure is attributable to the firm rather
than the consumer, if the firm could have prevented the failure from occurring, and if the failure
is likely to happen again (Bitner 1990; Folkes 1984). While the stability dimension is hard to
judge in our database, we can infer locus and controllability. Product-not-as-expected complaints
(type 8) imply that the customer takes at least some responsibility for the mistake; hence its
predicted impact on defection is modest. All other complaint types can substantially be attributed
to the firm (rather than to the customer) and are to a large extent controllable.1
These are
therefore predicted to have a large impact on the likelihood of defection. In particular, wrong
information (type 6) implies that the firm is explicitly accused by the customer, since it is
strongly attributed to and potentially controlled by the firm. Locus and controllability are
summarized in Table 1, together with the overall predicted effects of the eight complaint types
on customer defection.
Recovery types
Service recovery refers to the actions that a firm takes in response to service failures
(Grönroos 1988). Here, we examine recovery in the context of our data, using the terms recovery
and response interchangeably. We identify six mutually exclusive types of recovery: (1) reship,
(2) non-reship correction, (3) refund, (4) certificates, (5) extra compensation, and (6) no
1 One potential exception is late or no delivery (type 4), a failure which may be at least partially attributed to the delivery company instead of the retailer.
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recovery. Recovery types 1 and 2 are corrective recoveries (i.e., they fix the problem without
providing compensation), and types 3 and 4 are compensatory (Hoffman and Chung 1999).
These first four types describe basic recoveries; types 5 and 6 capture extraordinary positive and
negative firm responses, respectively. Our response categories are similar to those used by Tax,
Brown and Chandrashekaran (1998); additionally they are identifiable in complaint databases,
actionable, and involve clear cost-benefit tradeoffs. Table 2 presents these six recovery types,
their frequency of occurrence, the dimensions along which they differ, and their expected
effectiveness in preventing defection.
[Table 2 About Here]
Distributive, procedural and interactional justice aspects influence customer satisfaction,
trust and commitment (Smith, Bolton and Wagner 1999; Tax, Brown and Chandrashekaran
1998). Social exchange and equity theories predict that refusing recovery (type 6) leads to low
perceived fairness and repurchase intentions (Bitner, Booms and Tetreault 1990; Blodgett, Hill
and Tax 1997). Similarly, merchandise certificates and other non-monetary compensation like
free shipping on the next order (type 4, henceforth “certificates”) may lead to perceived injustice,
because customers are “forced” to return to the retailer at which they experienced the failure.
According to self-reported retention rates, certificates are “unacceptable” (Kelley, Hoffman and
Davis 1993). At the same time, it is this “forced” return aspect that could make certificates very
effective when considering observed behavior (Conlon and Murray 1996). Furthermore, whether
the customer’s return marks a one-time affair in order to redeem the certificate or the resumption
of the relationship is a critical issue we subsequently test in our data.
It is not yet clear which of the recovery types reship (type 1), non-reship correction (type
2), refund (type 3) or extra compensation (type 5) should be the most effective, because the
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literature contains several conflicting results (Davidow 2003). Hoffman and Chung (1999) find
that compensatory responses are more effective than corrective responses in two typical services
settings, but Kelley, Hoffman and Davis (1993) find the opposite in a general merchandise,
brick-and-mortar setting. Also the impact of extra compensation (type 5) has not been fully
explored (Davidow 2003). In typical services settings, excellent recoveries can result in more
loyal customers than in the hassle-free case (Hart, Heskett and Sasser 1990; Smith and Bolton
1998). At the same time, consistent with the equity principle, compensation may only work up to
a certain level (Davidow 2003; Smith, Bolton and Wagner 1999). Table 2 summarizes our
predictions: though no recovery (type 6) is expected to be least effective, there is no unequivocal
evidence that certificates (type 3) are more or less effective in preventing defection than the other
four recovery types.
Customer history
Customer history may play two roles. First, it may directly signal the customer's
propensity to defect, even if the focal event does not involve a complaint (Bolton 1998). Second,
it may indirectly affect defection via the customer’s reaction to a complaint incident (Smith and
Bolton 1998). Furthermore, we expect that recent past experiences may get more weight than
earlier ones since they are more salient (Bolton, Lemon and Bramlett 2006).
For the direct effect of past purchases and complaints, a lengthy and extensive purchase
history indicates a stable and satisfactory customer-firm relationship (Morgan and Hunt 1994);
hence we predict a lower likelihood of defection (Israel 2005). Similarly, past complaints may
signal a lower level of overall satisfaction (Kowalski 1996) and a higher likelihood of defection.
Furthermore, even a satisfied customer may drop out if saturation is reached and the firm’s
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products do not need to be bought anymore, especially if the products are easily stockpiled
(Reinartz and Kumar 2003); this implies that large purchase amounts increase the risk of
defection.
For the indirect effect of past purchases and complaints, the literature has found that
overall (prior) satisfaction affects the impact of a complaint incident on trust and commitment, as
more satisfied customers react less intensely (Tax, Brown and Chandrashekaran 1998).
Customers with a long purchase history assign more weight to past experiences and less weight
to new events (Bolton 1998); hence we predict that they are more forgiving toward complaint
incidents. Similarly, we predict that previous complaints will make customers less forgiving
(Smith and Bolton 1998). Lastly, we do not expect any indirect effect of past purchase amounts.
DATA
Our transaction and complaint data are from a major U.S. internet and catalog retailer; it
is ranked in the Top 50 largest direct marketers by Catalog Age and Internet Retailer and it sells
toys, novelties, and party supplies. It has a proactive 100% satisfaction policy, as stated on its
website, and can be contacted using a toll-free phone number and by email.
The data include 20,000 new customers who made their first purchase in one of the first
10 weeks of 2001 and are observed until June 30, 2003, i.e., at most 2.5 years since their initial
purchase. Customers made on average 1.3 repeat purchases (ranging from 0 to 25) and spent $57
on each order. The novel feature of our data is the complaint log file, which identifies the
customer, date, and a description of the voiced complaint as well as the firm’s response. There
are 922 complaints recorded from 805 customers (4% of total customers). Most complaints are
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voiced soon after a purchase: 18% of all complaints occur on the same day as a purchase and
80% occur within three weeks. We use content analysis to classify complaint incident
descriptions into the eight complaint types from Table 1 and six recovery types from Table 2.
We hired and trained two M.Phil. students to independently code the 922 complaint events. Their
mutual hit rate (Cohen’s kappa) was .85 (.82) for the complaint types and .76 (.70) for the firm
recoveries. Discrepancies were resolved by a third judge (one of the authors).
In order to identify separate complaint and recovery effects, there needs to be sufficient
variation in complaint-recovery pairs observed in the data. A strict firm protocol that always
assigns the same response to a specific complaint would make such parameter identification
difficult. To measure this in our data, we use the entropy index (Vermunt and Magidson 2005, p.
47), where 0 implies seemingly random firm responses (no protocol), and 1 means that every
complaint type is always addressed by one specific response (strict protocol). The actual value,
.25, confirms there is substantial variation in complaint-recovery pairs. We estimate a main
effects model and are cautious in interpreting only frequently observed complaint-recovery
combinations in our CLV calculations.
Our estimates may also suffer from endogeneity bias if the company’s willingness to
offer a favorable response to a complaint depends on customer history. We tested for this by
estimating an ordered logit model and found that a favorable outcome (low = no recovery,
medium = any of the four basic recoveries, high = extra compensation) is less likely if the
customer has complained before, while purchase history is not used in either direction. That is,
the firm does not treat new customers (who may be less valuable but more responsive, as in
Bolton 1998) and customers with a long purchase history (more valuable but less responsive)
differently. Hence, endogeneity is not expected to be a major issue in our empirical application.
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MODEL FOR PURCHASING, COMPLAINING AND DEFECTING
This section translates the conceptual framework into the empirical model (see Figure 1
for the connection between the steps and the equations below). The model describes when
customers purchase and complain, the amounts purchased, the types of complaint voiced, and the
likelihood of defection after any of the events. As indicated earlier, these components (with
margin and discount rates) are necessary to calculate CLV.
Step 1 in Figure 1 concerns event type (i.e. purchase or complaint) and event timing. The
joint type-timing density for repeat event j of active customer i is
(1) ( )( ) ( )( ) ( )( ) ( ), ,0 0
, , ,, 1 , if Z 1i j i jI y I y
i j p p i j c c i jf t f tπ α β π α β> =
− =
where ,Z 1i j = indicates that customer i has remained active after the previous event, a necessary
condition for event j to occur ( ,Zi j is updated in the defection component, discussed later on),
1, , ,( | , ) exp( [ / ] )i j i j i jf t t tα α αα β αβ β− −= − denotes the Weibull density of inter-event time ,t i j
with shape parameter 0α > and scale parameter 0β > , π is the probability that the event is a
purchase rather than a complaint, and ,i jy is the dollar amount spent: , 0i jy > indicates a
purchase, while , 0i jy = implies a complaint. In line with the customer base and purchase timing
literatures, we model the inter-event time as a continuous time process (measured in days). The
joint density in (1) is able to capture a crucial feature of complaints: they tend to occur
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infrequently (large π ) and with short interevent-times (with a corresponding Weibull density
mode close to zero).2
If a purchase occurs, the customer moves to step 2 and decides how much to spend (in
dollars) and whether to accompany the purchase with a complaint on the same day. We use a
gamma density to model purchase amounts since it is positive and right-skewed (Fader, Hardie
and Lee 2005). We use a two-component gamma mixture density because it provided markedly
better fit to the data than a single component. The dollar amount has density:
(2) ),~,~|()1(),|()0|( 21,21,,. λλπλλπ jigjigjiji yGyGYyg −+=>
where )(/)/exp(),|( 12,1
,221,11 λλλλλ λλ Γ−= −−
jijiji yyyG denotes the gamma density with shape
parameter 01 >λ and scale parameter 02 >λ , and gπ is the mixture weight. We model the
likelihood of a same-day complaint separately, since continuous-time models assign zero
probability to joint events and, as we mentioned earlier, purchases with same-day complaints
occur frequently. We model the probability of the purchase being accompanied by a same-day
complaint via a logistic function as
(3) ,)exp(1
1)0|0Pr( ,, κ−+=>> jiji YC
where parameter κ determines the frequency of joint occurrence. 0, =jiC implies that the event
does not involve a complaint, while 0, >jiC implies the presence of a complaint.
2 The joint density is the marginal probability of the event-type multiplied by the conditional density of timing. Alternatively, one could first formulate the marginal density of timing as a mixture of two Weibulls and multiply it by the conditional event-type probability, obtained by Bayes’ rule. This order results in the same joint density.
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If the customer complains, the customer moves to step 3 in Figure 1, which identifies the
complaint type }~,,1{ Cc ∈ . The probability of each type is defined by the multinomial logistic
specification
(4) .))ln()ln(exp(
))ln()ln(exp()0|Pr( ~
1~
2,~,2,~,1~,0
2,,2,,1,0
,,
∑=
++
++=>=
C
cjicjicc
jicjiccjiji
tt
ttCcC
γγγ
γγγ
The formulation in (4) is a flexible, non-monotonic function that allows the specific type of
complaint to depend on the number of days elapsed . For identification, the three parameters
1,0γ , 1,1γ and 1,2γ corresponding to complaint type 1 are set equal to zero.
Lastly, after any event, the customer moves to step 4 in Figure 1 and decides whether to
move to the permanent inactive state, i.e., defect, or stay with the firm for another round. The
defection probability is described by the logistic function
(5) ()
, 1 ,
, 1 , 2 , 3 ,
, , , ,1 1
Pr( 0 | 1)
LOGIST ( 0) PURCH_HIST COMPL_HIST AMOUNT_HIST
( 0) ( ) ( ) ,
i j i j
i j i j i j i j
C Ri j i j c i j r i jc r
Z Z
I c
I c I c c I r r
µ θ θ θ
ξ δ η
+
= =
= =
= + = + +
+ > = + = ∑ ∑� �
where )]exp(1/[)exp()LOGIST( ⋅+⋅=⋅ , and }~,,1{, Rr ji ∈ is the firm's actual response to a
complaint voiced by customer i in event j. For identification, the coefficient of firm response
type R~ (no recovery) is set at zero. The three customer history variables are measured as in other
studies (Ansari, Mela and Neslin 2008; Van Diepen, Donkers and Franses 2009):
ji,PURCH_HIST is a weighted count of past purchases, ji,COMPL_HIST is a weighted count of
past complaints, and ji,TAMOUNT_HIS is a weighted average of past purchase amounts. The
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weights of past events are empirically determined, depend on the number of days since
occurrence, and allow us to assess how long the impact of a previous event lasts. The
specification in (5) captures both the direct impact of customer history (i.e., if 0, =jic ) and the
indirect impact of how the customer reacts to a complaint incident (i.e., if 0, >jic ), where
recovery types are included as main effects. The multiplier3
(6) )TAMOUNT_HISCOMPL_HISTPURCH_HISTexp( ,3,2,1, jijijiji ωωωξ ++=
takes on positive values and uses the same three history variables as (5). It allows us to test
whether the likelihood of defection after a complaint is dampened (if 10 , << jiξ ), or magnified
(if 1, >jiξ ) by customer history. As indicated earlier, we expect that complainants react less
intensely if they have a longer purchase history ( 1 0ω < ) and more intensely if they have a
complaint history ( 2 0ω > ).
We extend the base model described by (1) to (6) with latent classes in order to account
for unobserved heterogeneity (Wedel and Kamakura 2000), where class },,1{ Ss ∈ has size
sψ such that 1
1Sss
ψ=
=∑ . We make all coefficients in (1) to (3) and the intercept in (5)
heterogeneous (Netzer, Lattin and Srinivasan 2008), and estimate all model parameters using
Maximum Likelihood4
(see Web Appendix A).
3 We have also checked whether a second multiplier should be included for firm response, but this did not result in an empirically better model specification. We therefore use the more parsimonious specification (5) as the focal model. 4 We assume homogeneity in (4), as there is no reason to expect significant differences in the complaint timing-type relationship across segments and for model parsimony reasons.
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RESULTS
Based on the BIC criterion, three segments are sufficient to capture unobserved
heterogeneity in purchasing, complaining and defecting. Web Appendix B provides the full set
of segment-specific parameter estimates (equations (1) to (3) and the intercept in (5)) and Web
Appendix C provides the estimates for the complaint type equation (4). Though the timing, event
type and amount-spent distributions in (1) to (4) are necessary to calculate CLV, our substantive
interest centers on the defection equation (5). Likelihood Ratio (LR) tests allow us to assess the
predictive importance of our complaint and firm recovery types in the defection equation.
Omitting both complaint and recovery components leads to a significantly worse fit than the full
model (LR=55.00, df=15, p<.001), as does removing the complaint component (LR=50.61,
df=10, p<.001) or the recovery component (LR=35.63, df=5, p<.001). Hence, complaint and
recovery types significantly enhance model fit. We next discuss the parameter estimates, and
illustrate how our framework can be used to assess the consequences of complaints and
recoveries for defection and CLV.
Which complaints lead to defection most?
Table 3 provides estimates for the defection equation (5), where positive coefficients
mean increases in the likelihood of defection, along with our predictions developed earlier. The
top part of the table shows that all complaint type coefficients are significant at 5%, while seven
out of eight are significant at 1%. The results are consistent with our predictions. Complaints
about perceived price issues ( 1δ = .87), order placement and billing issues ( 2δ = 1.34) and
product-not-as-expected ( 8δ = 2.14) have a modest impact on defection, while late or no delivery
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( 4δ = 3.54), wrong package contents ( 5δ = 2.84), wrong information ( 6δ = 3.29) and defective
product ( 7δ = 3.34) have larger effects. Out-of-stock ( 3δ = 4.08) has the largest effect of all
types, confirming survey-based and experimental findings that stock outs lead to diminished
loyalty (Goodman 2006) and likelihood of return (Fitzsimons 2000), but casting doubt on the
results of recall-based surveys (e.g., Kelley, Hoffman and Davis 1993). Taken together, our
complaint type estimates show that outcome failures have a larger impact than process failures
and that a failure attributable to the firm (e.g., defective product) has a larger impact than a
failure at least partially attributable to the customer (product-not-as-expected). The top part of
Figure 2 translates these effects into defection probabilities, while averaging over customer
history and firm response variables. The defection probabilities vary from .28 for perceived price
issues (type 1) to .46 for out-of-stock (type 3), whereas the defection probability after a purchase
without a complaint is .16.
[Table 3 and Figure 2 About Here]
Which recoveries are most effective?
The coefficients of the recovery types in the middle of Table 3 describe main effects and
are all negative (the base case is no recovery, type 6). They suggest that good recoveries matter
(all coefficients are significant at 1%). As predicted, no recovery is less effective than reship
( 1η = -1.21), non-reship correction ( 2η = -.91), refund ( 3η = -1.11) and extra compensation ( 5η = -
.96); this latter type is no more effective than the other three constructive recovery types. We
could not provide a strong prediction for merchandise certificates (type 4), but we reasoned that
they could encourage the recipient to “try” the company once more (consistent with the
estimated coefficient). Strikingly, such certificates have the most negative coefficient ( 4η = -
17
1.46); hence, they are the most effective recovery type considered here. But does this lead to a
sustained recovery or does the customer return one more time to cash in the certificate and
defect? To address this question, we added a dummy variable to the model indicating whether
certificates were provided during the previous event. The dummy coefficient was economically
small (d = .17) and statistically insignificant (p = .70), indicating that defection in the first
occasion after voicing a complaint and receiving certificates is not significantly different from
other purchase occasions. This amounts to a sustained recovery. The bottom of Figure 2
translates these recovery effects into defection probabilities, where customer history variables are
kept at their average values and complaint types have been averaged out. The defection
probabilities vary from .27 for certificates (type 4) to .60 for no recovery (type 6) and illustrate
the wide range of effectiveness.
How does customer history influence defection?
The smoothing coefficients of the three customer history variables are .998, .982 and
.982, respectively (Table 3), indicating that the recent past gets more weight (Bolton, Lemon and
Bramlett 2006). The impact of past purchases decays slowly, with a halving time of almost a
year ( =)998.0ln(/)5.0ln( 285 days), whereas past complaints are “forgotten” relatively quickly,
with a halving time of 38 days. The weights of past purchase amounts are also halved in 38 days.
Even if the current event does not involve a complaint, the customer's history directly
influences the probability of dropping out (see Table 3). As predicted, more past purchases
decrease the probability of defection ( 1θ = -1.04), whereas past complaints ( 2θ = .59) and average
purchase size ( 3θ = .0018) increase the probability of defection. Unless the customer decided to
defect after the previous complaint or a second failure occurs, the relationship returns quickly to
18
business-as-usual. The customer's history also indirectly influences defection if a complaint
occurs. Consistent with the conceptual framework, a long purchase history makes the customer
more forgiving and less likely to defect ( 1ω =-.89), while a second complaint intensifies the
customer’s determination to abandon the retailer ( 2ω = .77), especially if it occurs soon after the
first one. Both effects are significant at 1%. The effect of (weighted) average purchase amount
from previous transactions is not significant ( 3ω = -.00078). We did not have a prediction for this
coefficient.
The impact of recovery on CLV: two scenarios
The previous discussion suggests that customer complaints and firm recoveries can have
far-reaching consequences for CLV. We investigate this further by considering two failure-
recovery scenarios in more detail. The first corresponds to a complaint about late or no delivery,
which has the highest frequency in our data set (Table 1), is likely a representative failure for a
catalog and online retailer, has a large effect on defection (Table 3 and Figure 2) and is variously
dealt with by the firm. The top part of Table 4 provides three possible firm responses (no
recovery, refund and certificates) as well as a regular purchase as a benchmark. This allows us to
assess (1) the financial consequences of refusing to make any recovery, and (2) the effectiveness
of giving certificates rather than the other compensatory response, i.e. refund. We examine the
role of customer history by considering three possible complaint histories (no previous
complaints, recent and distant past complaint) as well as two possible purchase histories (new
and experienced customer).
[Table 4 About Here]
19
Columns 1 and 2 of Table 4 show the defection probabilities in the various scenarios. The
smallest probability is .03 for an experienced customer (i.e. 5 repeat purchases) without past
complaints who makes a regular purchase. The largest probability is .94 for a new customer (0
repeat purchases) who complained 7 days before the current complaint and for whom no
recovery effort is made. Consistent with earlier results, experienced customers are more
forgiving than new customers after a complaint incident. Columns 3 and 4 display simulated
CLV estimates, i.e. the net present value of the margins generated by the customer's purchases
after the complaint incident, using an annual discount rate of 12% and accounting for the average
margin rate in our data. If the firm provides no recovery, CLV is reduced from $90 to $50 for an
experienced customer, and is virtually wiped out for a new one. In all cases – except for a new
customer who has complained recently – certificates or a refund help to avoid a large drop in
CLV. Columns 5 and 6 give the difference in CLV between these recoveries and no recovery.
The monetary benefits of recovery are substantial for experienced customers and new customers
who have not complained before: they total about $22 for refund and $28 for certificates. Given
that the marginal benefit of certificates is non-trivial and firm costs are likely to be similar, this
calculation supports providing certificates over refunds.
As a second scenario, we consider a complaint involving a perceived price issue (e.g.,
expired promotional offer), which has the smallest effect on defection and is usually addressed
by the firm with a non-reship correction, with the second most frequent response being no
recovery. The bottom part of Table 4 shows the consequences for defection and CLV of these
two recovery types. The defection probability reveals a pattern similar to late or no delivery, but
with smaller values. Correcting even small failures matters: the drop in CLV due to a perceived
price issue is mitigated by about $20 if a correction is made rather than no recovery.
20
DISCUSSION AND CONCLUSION
In this study, we developed and tested a model for the effects of customer complaints
about product and service failures and firm recovery responses on defection and CLV. Our
results have implications for information systems, failure prevention and recovery strategies.
Complaint database management
Firms invest heavily in CRM systems that track customer-firm interactions over time
(Bolton, Lemon and Bramlett 2006). This implies that both transaction and complaint data are
typically available. As we have demonstrated them, combining these two sources can provide a
low-cost and powerful method to study the bottom-line effects of failure and recovery. In our
study, we relied on content analysis of verbal complaint descriptions. Retailers could make such
coding more efficient by electronic text-mining (Kanaracus 2008) or training customer service
representatives to use a consistent pre-set categorization system of complaint types and firm
responses. By encompassing the content analysis step, it may become feasible to build an
automated decision support system for financially accountable complaint management.
Failure prevention strategies
We find that failures related to stock-outs have the largest impact on defection. An
implication for retailers is to take pre-emptive measures to monitor and maintain adequate
inventory. In a similar vein, Blattberg and Deighton (1996) start their influential customer equity
paper by discussing an online and catalog retailer (Lands’ End) keeping “unusually” high
inventory levels in order to avoid stock-outs. Such a strategy may indeed be rewarding.
21
Furthermore, even the mildest failure type, perceived price issues, can lead to substantially lower
CLV than a regular purchase without such a complaint (usually occurring on the same day). For
instance, perceived price issues include promotional offers that have expired. The retailer could
both save resources and avoid the negative consequences for CLV by automatically granting a
small extension to the offer deadline, while not directly informing customers about it. Similarly,
a relatively modest investment in the retailer's website may be sufficient to mitigate order and
billing issues, a failure which has a defection probability roughly twice that of a hassle-free
purchase. Insights such as these are possible only with complaint types that reveal the specific
source of the failure, and linking them to defection and CLV.
Recovery strategies
Survey-based research classifies merchandise certificates as a bad recovery, based on
self-reported retention. Our results, based on tracking actual behavior, indicate that certificates
are on average the most effective recovery strategy since they reduce the likelihood of defection
most. Moreover, this effect leads to a sustained recovery rather than simply prolonging defection
for an extra purchase. Coupled with the result that the “memory” for past complaints fades
quickly, one implication for managers is that offering merchandise certificates to reset the
customer relationship is a surprisingly effective recovery strategy. At a minimum, if a retailer is
considering a compensatory recovery to handle a complaint, our results favor offering a
merchandise certificate over a refund. In general, the CLV calculations indicate that it is worth to
devote substantial resources to a constructive recovery. For instance, not correcting a complaint
about perceived price issues costs about $20 extra (reducing CLV by an extra 25%, see Table 4).
Since the cost of recovery by granting a deadline extension or free shipping is only a few dollars,
22
making such corrections is clearly rewarding. Similarly, not recovering a late delivery implies an
extra drop in CLV by about $25 (Table 4). Again, we expect the cost of a constructive recovery
to be substantially less. On the other hand, our results also suggest that it is usually not necessary
to provide extra compensation for the customer's hardship.
Further research
Our basic model is a first step toward financially accountable, data-based complaint
management. There are several avenues for further research. Most importantly, the sparsity of
complaint incidents in our data set limits the potential to test more complex models, such as
those that include interactions between complaint types and firm recoveries (Smith, Bolton and
Wagner 1999), structural models that capture customer expectations of response, or more
sophisticated psychological mechanisms that may underlie the consumer’s response.
Substantially expanding the data to include more customers or time periods may increase
statistical power and allow for testing such models. A second avenue would be to collect self-
reported perceptual measures, such as customer satisfaction, and merge them with longitudinal
purchase and complaint data (Gupta and Zeithaml 2006). Surveys combined with observed
behavior may comprise the backbone of any firm’s service-quality information system (Berry
and Parasuraman 1997), and allow for a more detailed assessment, especially distinguishing
recoveries that are effective at preventing defection from increasing satisfaction. Third, it would
be useful to develop an approach that accounts for word-of-mouth and other network effects
across customers (Gupta and Zeithaml 2006).
23
Conclusion
This study has shown how historical transaction data can be integrated with complaint
log files, by linking specific complaint types and firm recoveries to post-complaint purchasing
behavior and CLV. As such, it provides an initial but important step toward more financially
accountable complaint management in which the benefits of both failure prevention and recovery
are measured by their impact on the bottom line. The required data are typically available within
companies, and the approach has the potential to end up in decision support systems.
24
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28
Table 1
Classification of Complaint Types
Category Super1 Freq.2 Process /
Outcome Locus Control Predicted
Impact 1. Perceived price issues
PRI 14% Process Firm High Low
2. Order placement and billing issues
FUL 7% Process Firm High Low
3. Out-of-stock FUL 4% Outcome Firm High High
4. Late or no delivery FUL 21% Outcome Firm or third party
In between High
5. Wrong package contents FUL 18% Outcome Firm High High
6. Wrong information FUL 2% In between Firm Very high High
7. Defective product PRO 15% Outcome Firm High High
8. Product-not-as-expected PRO 18% Outcome Customer Low Low
1 Super-category: PRI = price, FUL = fulfillment, PRO = product. 2 Frequency of occurrence in the data, N = 922.
29
Table 2
Classification of Firm Recovery Types
Category Super1 Freq.2 Justice Return Trigger
Predicted Effectiveness
1. Reship COR 19% High Low
Moderate
2. Non-reship correction COR 27% High Low
Moderate
3. Refund (cash) COM 30% High Low
Moderate
4. Certificates (non-cash) COM 11% Low High
?
5. Extra compensation EXT 8% High Low
Moderate
6. No recovery EXT 4% Low Low
Low
1 Super-category: COR = corrective, COM = compensatory, EXT = extraordinary. 2 Frequency of occurrence in the data, N = 922.
30
Table 3
Defection Model Equation Results (eq. 5)
DV: Likelihood of Defection Parameter Estimate
Predicted Effect
Complaint Type1
δ1, Complaint Type 1: Perceived price issues 0.87* Low
δ 2, Complaint Type 2: Order placement and billing issues 1.34** Low
δ 3, Complaint Type 3: Out-of-stock 4.08*** High
δ 4, Complaint Type 4: Late or no delivery 3.54*** High
δ 5, Complaint Type 5: Wrong package contents 2.84*** High
δ 6, Complaint Type 6: Wrong information 3.29** High
δ 7, Complaint Type 7: Defective product 3.34*** High
δ 8, Complaint Type 8: Product-not-as-expected 2.14*** Low
Firm Recovery Type2
η1, Firm Response 1: Reship -1.21*** Moderate
η2, Firm Response 2: Non-reship correction -0.91*** Moderate
η3, Firm Response 3: Refund -1.11*** Moderate
η4, Firm Response 4: Certificates -1.46*** ?
η5, Firm Response 5: Extra compensation -0.96** Moderate
η6, Firm Response 6: No Recovery 0.003 Low
Customer History (Direct Effect) 4
θ1, Purchase history (smoothed) -1.04*** –
θ2, Complaint history (smoothed) 0.59* +
θ3, Amount history (smoothed) x 10-2 0.18*** +
Customer History (Indirect Effect) 4
ω1, Purchase history (smoothed) -0.89*** –
ω2, Complaint history (smoothed) 0.77** +
ω3, Amount history (smoothed) x 10-3 -0.78 ?
Model Fit Log-likelihood = -88,453 *** p < .001; ** p < .01; * p < .05. 1 Segment specific intercepts suppressed to save space. 2 Base case is no recovery, prediction concerns absolute value of negative coefficient. 3 Fixed at 0 for identification. 4 Corresponding smoothing coefficients are .998, .982 and .982, respectively. .
31
Table 4
Likelihood of Defection and CLV after Late or No Delivery and after Perceived Price
Issues, as a Function of Firm Recovery and Purchase-Complaint History
Likelihood of Defection Customer Lifetime Value (CLV)
Difference CLV due to recovery
Purchase History Purchase History Purchase History Current Event
Type Complaint History
(1) New1
(2) Experienced
(3) New
(4) Experienced
(5) New
(6) Experienced
Purchase only (No Complaint)
None2 0.26 0.03 71.37 89.34 -- -- Distant 0.29 0.04 68.60 89.13 -- -- Recent 0.37 0.05 61.79 87.99 -- --
Late or No Delivery
- No Recovery None 0.78 0.49 23.25 51.07 -- -- Distant 0.83 0.50 17.61 50.18 -- -- Recent 0.94 0.53 6.70 46.91 -- --
- Refund None 0.54 0.24 46.58 72.60 23.33 21.53 Distant 0.62 0.25 38.42 72.10 20.82 21.92 Recent 0.83 0.28 17.70 69.75 10.99 22.85
- Certificate None 0.45 0.18 54.64 77.40 31.39 26.33 Distant 0.54 0.18 46.51 77.06 28.90 26.88 Recent 0.78 0.20 23.31 75.14 16.61 28.23
Perceived Price None 0.53 0.45 47.29 54.34 -- --
- No Recovery Distant 0.55 0.45 45.23 54.24 -- -- Recent 0.62 0.46 38.97 53.41 -- --
- Non-Reship Correction
None 0.31 0.25 66.69 71.82 19.40 17.46 Distant 0.33 0.25 64.98 71.80 19.75 17.58 Recent 0.40 0.26 59.41 71.20 20.44 17.79
1 New = 0 repeat purchases; Experienced = 5 repeat purchases. 2 None = no past complaints; Distant = one complaint 70 days ago; Recent = one complaint 7 days ago.
32
Figure 1
Steps between the Customer’s Unobserved Active and Inactive States
stay
defect
no
yes
complaint purchase
Step 1 Time & Purchase
or complaint? [eq. 1]
Active state
Step 2 Purchase amount &
Immediate complaint? [eq. 2 - 3]
Step 3 Complaint type?
[eq. 4]
Step 4 Next state? [eq. 5 - 6]
Inactive state
33
Figure 2
The Likelihood of Defection for Complaint Types and Firm Recoveries
34
WEB APPENDIX
Web Appendix A: Derivation of Likelihood Function This appendix provides the log-likelihood function which is maximized in order to find
the parameter estimates. We discuss the model without heterogeneity. The extension with
heterogeneity is straightforward, and we refer to Wedel and Kamakura (2000) for the details. For
a given customer i, the likelihood function can be decomposed into three components, i.e. the
initial event, all repeat events, and the silent period after the last event until the end of the
observation period.
Initial event
The initial event 0=j involves a purchase by definition, and occurs at time 0. Therefore
the likelihood contribution of this event only considers the amount spent and a possible
immediate complaint of a given type. It is given by
( )
.)0|Pr(
)0|0Pr(1)0|0Pr()0|()(C~
1 ,,
)0(,,
)0(,,,.,initial
,
,,
ccI
c jiji
cIjiji
cIjijijijii
ji
jiji
CcC
YCYCYygL=
=
=>
∏ >=×
>>−>>>=
Repeat events
Repeat event },,1{ iNj ∈ involves the timing and type of this event as well as the
amount spent or the possible complaint type. Furthermore, event j can only occur if the customer
has not dropped out after event 1−j . The corresponding likelihood contribution
becomes
35
( ) ( ) ),,(,|()1(,|())1|0Pr(1( ,,)0(
,)0(
,1,,,repeat,,,
jijiyI
ccjiyI
ppjijijiji cyhtftfZZL jiji =>− −==−= βαπβαπ
where
( )( ).)0|Pr(
)0|0Pr(1)0|0Pr()0|(),()(C~
1 ,,
)0()0(,,
)0(,,,.,,
,
,,,
ccI
c jiji
yIcIjiji
cIjijijijijiji
ji
jijiji
CcC
YCYCYygcyh=
=
>=>
∏ >=×
>>−>>>=
Silent period after last event
The likelihood that no event has occurred in between the last observed event iN (with
timing ∑ =
iN
j jit1 , ) and the end of the observation period iT~ consists of two components: the
customer has either dropped out after event iN or has remained active with the next event
occurring beyond iT~ . This gives the likelihood contribution
( ) ,~))1|0Pr(1()1|0Pr(1 ,,1,,1,,silent ∑ =++ −==−+=== i
iiii
N
j jiiNiNiNiNii tTSZZZZL
with function S denoting the mixture-Weibull survival function counterpart of (1).
Overall likelihood
The overall likelihood for customer i is given by
,,silent1
,repeat,,initial i
N
jjiii LLLL
i
×
×= ∏
=
where by convention the empty product (running from 1=j to 0) has value one. After taking
logarithms and combining all M customers in the data set, the overall log-likelihood is given by
∑=
=M
iiLLL
1).ln(
36
Web Appendix B: Segment Specific Parameter Estimates Segment 1 Segment 2 Segment 3
Defection Equation (5)
µ , Intercept 0.007 -0.471*** -0.419***
Event Timing and Type (1) 1
pα , Shape parameter, 1st mixture component 0.905*** 0.959*** 0.844***
pβ , Scale parameter, 1st mixture component 2.722*** 2.665*** 2.029***
cα , Shape parameter, 2nd mixture component 0.643*** 2.548*** 0.923***
cβ , Shape parameter, 2nd mixture component 0.856*** 0.122*** 0.219***
π , Mixture weight 0.985*** 0.980*** 0.955***
Purchase Amount (2) 2
1λ , Shape parameter, 1st mixture component 3.509*** 62.359*** 2.117***
2λ , Scale parameter, 1st mixture component 0.069*** 0.010*** 0.443***
1λ , Shape parameter, 2nd mixture component 2.051*** 2.834*** 1.085***
2λ , Scale parameter, 2nd mixture component 0.317*** 0.187*** 2.274***
gπ , Mixture weight 0.861*** 0.058*** 0.842***
Complaint on Same Day as Purchase (3)
κ , Intercept -5.943*** -5.667*** -4.046***
Segment Weights
sψ , Segment size 0.441 0.382 0.177 *** p < .001; ** p < .01; * p < .05. 1 Timing is measured as number of days divided by 100. 2 Purchase amount is measured as dollars divided by 100.
37
Web Appendix C: Complaint Type Parameter Estimates From (4)
DV: Likelihood of Voicing a Specific Complaint Parameter Estimate
Complaint Type 2: Order placement and billing issues1
γ0,2, Intercept -1.094***
γ1,2, Coefficient of log time since last purchase 0.519*
γ2,2, Coefficient of log time squared since last purchase -0.063
Complaint Type 3: Out-of-stock
γ0,3, Intercept -2.399***
γ1,3, Coefficient of log time since last purchase 1.407***
γ2,3, Coefficient of log time squared since last purchase -0.220***
Complaint Type 4: Late or no delivery
γ0,4, Intercept -1.853***
γ1,4, Coefficient of log time since last purchase 2.370***
γ2,4, Coefficient of log time squared since last purchase -0.374***
Complaint Type 5: Wrong package contents
γ0,5, Intercept -1.908***
γ1,5, Coefficient of log time since last purchase 2.265***
γ2,5, Coefficient of log time squared since last purchase -0.347***
Complaint Type 6: Wrong information
γ0,6, Intercept -3.340***
γ1,6, Coefficient of log time since last purchase 1.981***
γ2,6, Coefficient of log time squared since last purchase -0.351***
Complaint Type 7: Defective product
γ0,7, Intercept -1.886***
γ1,7, Coefficient of log time since last purchase 1.871***
γ2,7, Coefficient of log time squared since last purchase -0.248***
Complaint Type 8: Product-not-as-expected
γ0,8, Intercept -1.482***
γ1,8, Coefficient of log time since last purchase 1.662***
γ2,8, Coefficient of log time squared since last purchase -0.209*** *** p < .001; ** p < .01; * p < .05. 1 Parameter estimates for complaint type 1 fixed at zero for identification.