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MARKETING PERSUASION TECHNIQUES

40 Cornell Hotel and Restaurant Administration Quarterly APRIL 2002

© 2002, CORNELL UNIVERSITY

The Science and Practiceof Persuasion

From business owners to busboys, the ability to harness the power of persuasion is often anessential component of success in the hospitality industry.

BY ROBERT B. CIALDINI AND NOAH J. GOLDSTEIN

Simply put, in general people are inclined to favor and tocomply with those whom they like. A good illustration of thisfundamental principle of influence in action is the Tupperwareparty, in which salespeople invite their friends and neighborsto their homes to pitch useful household plastic products. Astudy done by Frenzen and Davis confirmed what theTupperware Corporation knew all along: guests’ liking for theirhostess was twice as important as was their opinion of theproducts in influencing their purchase decisions.2

In the case of the Tupperware party, the seller is not just alikeable person, but is probably a friend and respected com-munity member as well. The power of the “liking” principle

1 See also: Harsha E. Chacko, “Upward Influence: How AdministratorsGet Their Way,” Cornell Hotel and Restaurant Administration Quarterly,Vol. 29, No. 2 (August 1988), pp. 48–50.

2 Jonathan K. Frenzen and Harry L. Davis, “Purchasing Behavior in Em-bedded Markets,” Journal of Consumer Research, Vol. 17 (1990), pp. 1–12.

Research reveals that there are six basic principles thatgovern how one person might influence another.Those principles can be labeled as: liking, reciproca-

tion, consistency, scarcity, social validation, and authority.1

In the pages that follow we elaborate on each of those sixprinciples and highlight some of their applications in thehospitality industry—for instance, how a restaurant managermight reduce the reservation no-show rate by two-thirds; howto influence the size of the gratuity patrons leave for theirservers; how to encourage customers to order additional foodwhen they do not really want it; and how to get customers tocomply with employees’ reasonable requests.

APRIL 2002 Cornell Hotel and Restaurant Administration Quarterly 41

PERSUASION TECHNIQUES MARKETING

is so pervasive, however, that even perfect strang-ers can recognize whether there is any affinitybetween them within a relatively short time. Re-searchers have identified four primary determi-nants of our fondness for another person: physi-cal attractiveness, similarity, cooperation, and theextent to which we feel the person likes us.

Looking good. Most of us acknowledge thatthose who are physically attractive have a social ad-vantage held by few others, but evidence suggeststhat we have grossly underestimated the degree towhich that is true. For example, good-looking can-didates received more than two-and-a-half timesas many votes as did unattractive candidates in the1974 Canadian federal elections, despite the factthat most voters adamantly denied that attrac-tiveness had any influence on their decisions.3

One possible explanation for such findings isthat we tend to view attractive individuals aspossessing numerous other positive qualities thatwould be considered relevant to our likingthem—such as talent, kindness, honesty, andintelligence.4 One practical (and unfortunate)result of the “attractiveness” principle is that less-attractive individuals who rely heavily on tips forincome may have to work especially hard to gaincustomers’ affection, approval, and cash.5

The social and monetary rewards that beauti-ful people garner extend far beyond those ben-efits; they are also more successful at elicitingcompliance with their requests. Reingen andKernen found that an attractive fundraiser forthe American Heart Association collected almosttwice as many donations as did less-attractiveindividuals.6 That finding suggests that train-

ing programs in the hospitality industry couldincrease the effectiveness of trainees by includ-ing, for instance, grooming tips.

Simpatico. Similarity is another importantfactor that affects our liking for others. The ef-fects of similarity—however superficial—can bequite astounding because of the instant bond thatsimilarity can create between two people. Con-sider that in one study a fundraiser on a collegecampus more than doubled the contributionsreceived by simply adding the phrase “I’m a stu-

dent, too” to the request.7 Just as salespeople aretrained to find or even manufacture links betweenthemselves and their prospective clients, individu-als whose livelihoods depend on quick-formingrapport with their customers—such as food serv-ers or valets—may enhance their earnings sim-ply by pointing out a connection between them-selves and their guests. “Hold the mayonnaise?Yeah, I don’t eat it very often myself,” and “Wow,you’re from Chicago? My wife is from just southof there. She sure doesn’t miss the winters” areexamples of commonplace attempts to create sucha bond.

Similarities need not be overtly called to theother individual’s attention to obtain the desiredcompliance. Researchers found that a person wassignificantly more likely to receive a requesteddime from a stranger when the two were dressedsimilarly than when they were not.8 Since themajority of workers in the restaurant and hospi-tality industry wear uniforms, this subtle form

The six basic principles that govern how

one person might influence another are:

liking, reciprocation, consistency, scarcity,

social validation, and authority.

3 M.G. Efran and E.W.J. Patterson, “The Politics of Ap-pearance,” unpublished paper, University of Toronto, 1976.

4 For a review, see: Alice H. Eagly, Wendy Wood, and ShellyChaiken, “Causal Inferences about Communicators andTheir Effect on Opinion Change,” Journal of Personality andSocial Psychology, Vol. 36 (1978), pp. 424–435.

5 For evidence of the pervasiveness of this discrepancyin the salaries of North Americans, see Daniel S.Hammermersh and Jeff E. Biddle, “Beauty and the LaborMarket,” The American Economic Review, Vol. 84 (1994),pp. 1174–1194.

6 Peter H. Reingen and Jerome B. Kernen, “Social Percep-tion and Interpersonal Influence: Some Consequences ofthe Physical Attractiveness Stereotype in a Personal Sell-ing Setting,” Journal of Consumer Psychology, Vol. 2, No.1 (1993), pp. 25–38.

7 Kelly R. Aune and Michael D. Basil, “A Relational Obli-gations Approach to the Foot-in-the-mouth Effect,”Journal of Applied Social Psychology, Vol. 24, No. 6 (1994),pp. 546–556.

8 Tim Emswiller, Kay Deaux, and Jerry E. Willits, “Similar-ity, Sex, and Requests for Small Favors,” Journal of AppliedSocial Psychology, Vol. 1 (1971), pp. 284–291.



of persuasion may be rare. As a notable excep-tion, however, many waiters and waitresses at onepopular restaurant chain wear a myriad of but-tons pertaining to their interests on their uni-forms, at least some of which are likely to matchthe backgrounds and interests of their guests.

Allies. Cooperation has also been shown toengender feelings of liking, even between partiesthat previously exhibited mutual animosity.Muzafer Sherif and his colleagues found that pre-existing disdain between two groups of childrenat a camp was transformed into affection afterthey worked together to accomplish a necessary,mutual goal.9 One would hope that food serverswould start off on a better footing with theirguests than the children in Sherif ’s study had withone another, so an air of cooperation should al-ready exist. However, just as car salespeople “goto war” with their managers on behalf of theirclients, some food servers benefit by makingthemselves seem particularly cooperative withtheir guests: “You want more chips and salsa, sir?Well, the manager normally asks us to chargeextra for that, but I’ll see whether I can get yousome at no charge.”

Our fondness for another person also dependson the extent to which we believe the other per-son likes us. Just ask Joe Girard, the world’s great-est car salesman for 12 years in a row (accordingto the Guinness Book of World Records). One se-cret to his success may lie in a simple greetingcard that he sent to all 13,000 of his former cus-tomers every single month. Although the holi-day theme of each month’s card differed, the textnever varied. Other than his name, the only wordswritten on the card were, “I like you.”10

As a general rule we tend to like and to bemore willing to comply with the requests of thosewho show they are partial to us.11 Interestingly,one study revealed that a flatterer’s laudatory com-ments engendered just as much liking for the

sweet-talker when the remarks were false as whenthey were correct.12 Thus, praise is one way forfood servers to show their fondness for their cli-entele—and thereby to increase their tips. Hav-ing pointed that out, however, servers would bewise to proceed with caution—or better yet, withhonesty—because the “praise” tactic runs the riskof backfiring if guests perceive servers’ commentsto be a duplicitous attempt to manipulate them.

Researchers have established that there are anumber of fairly basic strategies servers can useto increase the average gratuity they receive by atleast 20 percent. Many of those strategies use thesimplicity of the liking principle. Squatting, smil-ing, and occasional touching, for example, helpto build a friendly rapport, while writing “thankyou” and drawing a happy face on the bill arepresumably signals to patrons that they are likedand that their waiter or waitress was especiallyhappy to serve them.13

It is important to note that these techniquesare not necessarily additive and that the appro-priateness of each strategy varies depending on anumber of factors, including the type of eatingestablishment, the disposition of each guest, andeven the gender of the food server.14 For example,waitresses who drew smiling faces on their cus-tomers’ checks significantly increased average tipsize by 18 percent.15 No significant difference wasfound for their male counterparts, however. Ifanything, the smiley-face strategy actually back-fired when used by waiters. Due to perceived vio-lations of gender-based expectations, it appearsthat for males, drawing a smiling face on thecheck may very well draw out a frowning facefrom the guests.

9 Muzafer Sherif, O.J. Harvey, B.J. White, W.R. Hood,and C.W. Sherif, Intergroup Conflict and Cooperation: TheRobbers’ Cave Experiment (Norman, OK: University of Okla-homa Institute of Intergroup Relations, 1961).

10 Robert B. Cialdini, Influence: Science and Practice, fourthedition (Boston, MA: Allyn & Bacon, 2001).

11 Ellen Berscheid and Elaine Hatfield Walster, InterpersonalAttraction (Reading, MA: Addison-Wesley, 1978).

12 See: David Drachman, Andre deCarufel, and Chester A.Insko, “The Extra-credit Effect in Interpersonal Attraction,”Journal of Experimental Social Psychology, Vol. 14 (1978),pp. 458–467; and Donn Byrne, Lois Rasche, and KathrynKelley, “When ‘I Like You’ Indicates Disagreement,” Jour-nal of Research in Personality, Vol. 8 (1974), pp. 207–217.

13 For a review, see Michael Lynn, “Seven Ways to IncreaseServers’ Tips,” Cornell Hotel and Restaurant AdministrationQuarterly, Vol. 37, No 3 (1996), pp. 24–29.

14 Ibid.

15 Bruce Rind and Prashant Bordia, “Effect of RestaurantTipping of Male and Female Servers Drawing a Happy,Smiling Face on the Backs of Customers’ Checks,” Jour-nal of Applied Social Psychology, Vol. 26, No. 3 (1996),pp. 218–225.



The positive results from using a

variety of persuasion techniques

are not necessarily additive.

ReciprocationA Chinese proverb states, “Favors from othersshould be remembered for a thousand years.” Themaxim succinctly emphasizes the importance ofthe norm of reciprocity—that we are obligatedto repay others for what we have received fromthem—in all human societies. The norm pushesus toward fairness and equity in our everydaysocial interactions, our business dealings, and ourclose relationships, while it helps us build trustwith others. At the same time, however, it alsoleaves us susceptible to the manipulations of thosewho wish to exploit our tendencies to achieveinequitable personal gains.

An informative study of the reciprocity prin-ciple and its potential to be exploited was con-ducted by Dennis Regan in 1971.16 In the ex-periment, individuals who received a small,unsolicited favor from a stranger (“Joe”) in theform of a can of Coca-Cola purchased twice asmany raffle tickets from Joe as those who receivedno favor at all. This occurred even though thefavor and the request took place one-half hourapart, and that Joe made neither implicit nor ex-plicit reference to the original favor when he madehis pitch about the raffle tickets. Interestingly,despite all that we have stated about the strongassociation between liking and compliance,Regan found that individuals who received aCoke from Joe made their purchase decisionscompletely irrespective of the extent to whichthey liked him. That is, those who didn’t like Joepurchased just as many raffle tickets as those whodid like him if they were the recipients of the giftearlier on. Thus, we see that the feelings of in-debtedness caused by the power of the reciproc-ity manipulation are capable of trumping the ef-fects of the liking principle.

While we have so far established that the normof reciprocity is powerful, the principle’s truepower comes from its ability to create situationsin which unequal exchanges take place. Reganfound that on average, the Coke-bearing strangerhad a 500-percent return on his investment,hardly an equal exchange at all!

16 Dennis T. Regan, “Effects of a Favor and Liking on Com-pliance,” Journal of Experimental Social Psychology, Vol. 7(1971), pp. 627–639.

Corporations and fundraisers alike have beenaware of the power of reciprocity for many years,and have attempted to use those principles withthe public. The Disabled American Veterans or-ganization, a charitable group that seeks dona-tions via fundraising letters, for example, in-creased its average response rate from 18 percentto 35 percent simply by enclosing a small gift inthe envelope.17 The new addition—a set of per-sonalized address labels—caused the recipientsto feel an immediate sense of obligation to repay

17 Jill Smolowe, “Read This!!!!!!!!,” Time, Vol. 136, No. 23(November 26, 1990), pp. 62–70.

18 See: Michael Lynn, “Restaurant Tipping and Service Qual-ity: A Tenuous Relationship,” Cornell Hotel and RestaurantAdministration Quarterly, Vol. 42, No 1 (February 2001),pp. 14–20.

the organization, despite the fact that the gift wasinexpensive to produce and the recipients neverasked for it in the first place.

Individuals in the hospitality, travel, and tour-ism industries are also in an appropriate positionto harness the power of the reciprocity principle.After all, tipping in the U.S. service industryis supposed to be based on a reciprocity-relatedquid pro quo system, in which it is tacitly acknowl-edged that the consumer will make a moregenerous payment in exchange for better-than-average service. Although the strength of the ac-tual relationship between service and tipping hasbeen challenged,18 it is clear that food-serviceworkers and others who rely heavily on tips standto benefit substantially by providing better over-all service; specifically, the server should make“additional” efforts that at least slightly exceedcustomer expectations. For example, Lynn andGregor showed that a bellman nearly doubledhis tip earnings by adding three simple and seem-ingly inconsequential steps to his standard du-ties: He showed the guests how to operate thetelevision and thermostat, opened the drapes to



expose the room’s view, and offered to bring theguests ice from the machine down the hall.19

Tip tips. The above example illustrates thesuccess of an individual who essentially made alow-risk investment that often paid big dividends.Food servers can take advantage of the reciproc-ity principle, too.20 In one study it was shownthat tips were higher when the servers allowedeach guest to select a fancy piece of chocolate atthe end of the meal than when no offer was made.Given that finding, we can see that the propri-etor of the first dine-in Chinese restaurant to servefortune cookies at the end of the meal made aclever and profitable decision. Unfortunately forthe wait staff in Chinese restaurants today, pa-trons have come to see a fortune cookie at theend of a meal as part of the experience—that is,as more of a right than a privilege or extra treat.

A second study by the same researchers showedthat allowing the guests to select two relativelyinexpensive pieces of chocolate proved even morefruitful than when the server offered just one.21

More revealing, the server who offered two pieceswas most successful when she first offered eachguest one piece of candy, gestured as if she wasabout to leave the table, and then let each guestchoose one more piece ofchocolate, as opposed towhen she simply allowed theguests to choose both piecesat once. It seems likely thatthe guests in the “1+1” con-dition assumed that thewaitress was making an ex-tra effort beyond what wasnormally required of her bythe managers, possibly be-cause she liked these dinersmore than she did most ofher guests. These findingssuggest that hotel house-

keepers who leave mints on pillows may be therecipients of larger tips than those who do not,but that they may be even more successful byplacing several extra mints on top of a personalthank you note the day before their guests checkout.

Hotel managers might find the use of the reci-procity norm especially helpful when appealingto guests to reuse towels and linens in an effortto conserve energy and resources. Currently, mostpleas take approaches that either educate theguests regarding the total amount of energy nec-essary to clean those items daily for a year, orinvoke the guests’ sense of social responsibility.Some hotels emphasize the benefit to themselvesin their appeals; few guests, however, will bemotivated to give up their clean sheets inexchange for a clean getaway by the hotel ownerwith the profits gained from such compliance.Perhaps in addition to one of the other twoappeals mentioned, hotel managers may achievea higher rate of participation by extending areciprocation-based approach in the form of apromise to donate a portion of the money savedto an environmental-conservation organizationor any other cause deemed worthy. For example,

the Windows of Hope Fam-ily Relief Fund, an organi-zation that provides aid tothe families of those in thefood-service profession whowere victims of the WorldTrade Center tragedy, suc-cessfully used this principlein an event dubbed Dine-Out, which took place onthe day exactly one monthafter the attack. More than4,000 restaurants through-out the world participatedand agreed to donate at least10 percent of that evening’s

sales to the fund, which both raised millions ofdollars for the charity and dramatically increasedmany of the participating restaurants’ businessfor that night and potential beyond.

Bargaining. While the rule of reciprocity mostoften takes the form of gifts or favors, a specificapplication of the principle is frequently used inthe negotiation process, which involves recipro-

“Favors fromothers should beremembered for athousand years.”

—Chineseproverb

19 Michael Lynn and Robert Gregor, “Tipping and Service:The Case of the Hotel Bellman,” Hospitality Management,Vol. 20 (2001), pp. 299–303.

20 David B. Strohmetz, Bruce Rind, Reed Fisher, andMichael Lynn, “Sweetening the Till—The Use of Candy toIncrease Restaurant Tipping,” Journal of Applied Social Psy-chology, Vol. 32, No. 2 (2002), pp. 300–309.

21 Ibid.



cal concessions. That is, if Person A rebuffs a largerequest from Person B, and Person B then con-cedes by making a smaller request, Person A willfeel obligated to reciprocate this concession witha concession of his or her own by agreeing to thislesser plea.

The first author and his colleagues conducteda study to examine this phenomenon in the mid-1970s.22 Half of the students in the experimentwere approached on a college campus walkwayand asked if they would agree to chaperonejuvenile-detention-center inmates on a daytrip to the local zoo; relatively few (17 percent)responded in the affirmative. The other half ofthe students were asked a different question first;a plea was made for them to volunteer as a coun-selor for these inmates for two hours per weekfor the next two years. Not surprisingly, every-one who heard this appeal refused to participate.But when this same group was then asked if theywould agree to chaperone the inmates at the one-time-only day trip to the zoo, the compliancerate for this smaller request was nearly triple thatof the half who were never approached with thelarger plea.

Some hotel managers make use of this ap-proach when negotiating deals for conventionsand banquets by holding back in their initial of-fer so that they can later appear to concede tothe client a number of amenities not present inthe original proposal. The assumption in this caseis that the client will feel the need to reciprocatethis concession by accepting the deal withoutmaking any more demands. Similarly, manymanagers start off the bargaining process withhigher-than-desired price quotes in anticipationof having to shave off from the total charge dur-ing negotiations.

ConsistencyPrior to 1998, Gordon Sinclair, the owner of aprominent Chicago eatery, was too often the vic-tim of a common occurrence in the restaurantbusiness: the dreaded reservation no-show. Onaverage, approximately 30 percent of all would-

be patrons who called for reservations failed toappear and never bothered to notify the restau-rant with a statement of cancellation. One day,Sinclair thought of a way that might minimizethe problem, so he asked his receptionists to makea few slight modifications in the reservation-taking procedure. Instead of ending their phonecalls with “Please call if you have to change yourplans,” Sinclair instructed the receptionists to ask,“Will you please call if you have a change to yourplans?” and then to pause for a moment to allowthe caller to respond. Once the new strategy wasimplemented, the no-show-no-call rate droppedfrom 30 to 10 percent.

Sinclair’s technique was successful because ittook advantage of a fundamental human ten-dency to be and to appear consistent with one’sactions, statements, and beliefs. This principlewas illustrated in a study that found that resi-dents who accepted and agreed to wear a smalllapel pin supporting a local charity were signifi-cantly more likely to make donations to that char-ity during a fundraiser at a later date than thosewho had not been approached before the dona-tion drive took place.23 Those who had previouslybeen induced to make public commitments tothat charity felt compelled to act consistently withthese commitments and to support it later on.Similarly, those who called for reservations andmade a public commitment regarding their fu-ture actions felt obligated to be consistent withtheir statements and to live up to their pledges.

Dessert first. Some shrewd servers benefitfrom their keen understanding of this principleby drawing out commitments from their guestsregarding potential dessert purchases when thepatrons (and their stomachs) are at their mostvulnerable. At one restaurant in particular, im-mediately following the introduction, some foodservers enthusiastically ask, “Who here is gettingcheesecake tonight?” After each person gives anaffirmative response—an action that originatesnot from the brain, but the belly—the server thengoes through the standard procedures. Once ev-eryone at the table is feeling full and bloated af-ter completing the main course, their server

22 Robert B. Cialdini, Joyce E. Vincent, Stephen K. Lewis,José Catalan, Diane Wheeler, and Betty Lee Darby, “Re-ciprocal Concessions Procedure for Inducing Compliance:The Door-in-the-face Technique,” Journal of Personalityand Social Psychology, Vol. 31 (1975), pp. 206–215.

23 Patricia Pliner, Heather Hart, Joanne Kohl, and DorySaari, “Compliance without Pressure—Some Further Dataon the Foot-in-the-door Technique,” Journal of Experimen-tal Social Psychology, Vol. 10 (1974), pp. 17–22.

The rule of“reciprocity”most oftentakes the formof gifts or fa-vors, and thatprinciple also isfrequently usedin businessnegotiations.



comes back, reminds the guests of their earliercommitments in a non-threatening, jovial man-ner, and begins to make dessert suggestions. Inthe end, despite initial urges to decline—tenden-cies that now originate from a full belly, the brain,and the wallet—many patrons still feel obligatedto say yes.

ScarcityIn the early 1970s Stephen West discovered thatundergraduates’ ratings of a University of Wis-consin campus cafeteria rose significantly within

a nine-day span of time.24 Surprisingly, the dif-ference in opinion had nothing to do with achange in the quality of the eatery’s food or ser-vice, but rather with its availability. Before thesecond set of ratings were assessed, studentslearned that due to a fire they would not be ableto eat there for the next two weeks.

Whether it’s an unavailable eating establish-ment, the last piece of apple pie, the only remain-ing convertible in a rental company’s lot, the lastlobster in the tank, the only hotel room with abalcony that’s still vacant, or the final unclaimedblanket on an airplane, items and opportunitiesthat are in short supply or unavailable tend to bemore desirable to us than those that are plentifuland more accessible.25 This often adaptive men-tal shortcut is one that naturally develops, sincewe learn early on in our lives that things existingin limited quantities are hard to get, and thatthings that are hard to get are typically better thanthose that are easy to get.26

Act now! Marketing strategists and compli-ance practitioners take advantage of the scarcityprinciple by emphasizing that their products arein limited supply, available for a limited time only,or are one-of-a-kind—often without regard tothe veracity of those claims. Although assertionsregarding availability status are in many casesspurious, businesses frequently employ scarcity-based marketing strategies legitimately in a genu-ine effort to make their offers more attractive.Lower rates for plane flights, hotel rooms, cruises,tours, and vacation packages are especially likelyto be justifiably advertised as “limited time only”and “in limited supply” because such offers tendto be made for the small pockets of time whenbusiness would otherwise be slower.

Proprietors of nightclubs and restaurants canalso make use of those principles by artificiallylimiting the availability of space. Nightclub own-ers, for example, commonly restrict the numberof people allowed inside even though there isplenty of space for more, not due to concernsregarding maximum occupancy laws, but becausethe apparent inaccessibility of the clubs makesthese establishments seem more desirable. Sim-ilarly, some restaurant managers limit the actualnumber of seats available to use the power ofscarcity.

The domains in which the scarcity principleoperates are not just limited to products andopportunities, but to information, as well. Re-search has shown that information that is ex-clusive is seen as more valuable and more per-suasive. For instance, a former doctoral studentof the first author showed that wholesale beefbuyers more than doubled their orders whenthey were informed that a shortage of Austra-lian beef was likely due to weather conditionsoverseas.27 When those purchasers were toldthat the information came from an exclusivesource at the Australian National Weather Ser-vice, however, they increased their orders byan astounding 600 percent. In this case theinformation regarding the upcoming shortageswas true, but one can imagine the potential

24 Stephen G. West, “Increasing the Attractiveness ofCollege Cafeteria Food: A Reactance Theory Perspective,”Journal of Applied Psychology, Vol. 60 (1975), pp. 656–658.

25 Michael Lynn, “Scarcity Effects on Value,” Psychology andMarketing, Vol. 8 (1991), pp. 43–57.

26 Michael Lynn, “Scarcity Effect on Value: Mediated byAssumed Expensiveness,” Journal of Economic Psychology,Vol. 10 (1989), pp. 257–274.

27 Amram Knishinsky, “The Effects of Scarcity of Materialand Exclusivity of Information on Industrial Buyer-perceived Risk in Provoking a Purchase Decision,” Ph.D.dissertation, Arizona State University, 1982.

In general, items and opportunities that arein short supply or unavailable tend to bemore desirable to consumers than are thoseitems that are plentiful and more accessible.



for abuse of this principle, given its dramaticeffectiveness. Thus, we should question anysituation in which an individual claims thathe or she is supplying us—and only us—witha certain piece of information.

Up to this point we have explained the scar-city principle in terms of the mental shortcut itprovides between something’s availability and itsquality. There is another factor at work here aswell, and it is related to the idea that as opportu-nities become less available, we lose freedoms.According to Jack Brehm’s well-supported theoryof psychological reactance, whenever our free-doms are threatened or restricted, we vigorouslyattempt to reassert our free choice, with a spe-cific focus on retaining or regaining exactly whatwas being limited in the first place.28

A study conducted by Reich and Robertsonsuggests that a sign posted next to the hotel poolthat reads, “Don’t You Dare Litter” or even just“Don’t Litter” is likely to backfire, especially withregard to young, unsupervised children. Instead,a less-strongly phrased message that emphasizesthe social norm, such as “Keeping the Pool CleanDepends on You,” stands the greatest chance ofsuccess.29 Similar results were found in anotherstudy that showed that high-threat anti-graffitiplacards placed in restroom stalls were defacedto a greater extent than were the low-threat plac-ards.30 Thus, some proprietors of bars—whoserestrooms are particularly susceptible to such van-dalism—stand to benefit by replacing messagesthat may be perceived as hostile or threateningwith more moderate pleas.

Social ValidationEarlier we described how some nightclub own-ers make their businesses appear more desirableby restricting the number of individuals allowedin at any one time. The secret of the success ofthis policy lies not only in its manipulation of

scarcity, but also in its use of the principle of so-cial validation, which asserts that we frequentlylook to others for cues on how to think, feel, andbehave, particularly when we are in a state of un-certainty.

Before returning to the example of a night-club, an examination of a study done by PeterReingen should prove informative.31 In the ex-periment, a group of researchers posing asfundraisers went door-to-door to solicit dona-tions for a local charity. As part of their request,the purported fundraisers showed homeownersa list of neighbors who had already agreed todonate to that particular cause. The experimentrevealed that the likelihood of donation was posi-tively correlated with the length of the list ofnames.

Just as many of those in the Reingen studydecided how they would act based on the num-ber of people they thought were engaging in thesame behavior, individuals selecting where theywould like to spend their time and money for anevening often use the number of others partici-pating in a particular activity to gauge the popu-larity—and thus, the worthiness—of that activ-ity. Since club operators limit the rate at whichthe inbound traffic moves, a figurative gridlockoccurs, producing long lines of people waitingfor their turn to move forward and into the club.As a result, passersby view the large crowd of in-dividuals waiting to get in as evidence of the club’svalue. In this case, quantity is believed to be atrue indicator of quality: If that many people arewilling to endure the wait to get in, it must re-ally be worth it.

In like manner, bartenders and live entertain-ers sometimes seed their tip jars with a numberof bills in an attempt to manipulate patrons’ per-ceptions of the tipping norm. Consider the dif-ference in the messages conveyed by a jar filledthree-fourths of the way to the top with one- andfive-dollar bills, versus a jar completely devoidof anything, except a nickel and seven pennies, aticket stub from the movie Ishtar, and an EastGerman Deutschmark. The former indicates thattipping—specifically, with bills—is the norm and

28 Jack W. Brehm, A Theory of Psychological Reactance (NewYork: Academic Press, 1966).

29 John W. Reich and Jerie L. Robertson, “Reactanceand Norm Appeal in Anti-littering Messages,” Journal ofApplied Social Psychology, Vol. 9, No. 1 (1979), pp. 91–101.

30 James W. Pennebaker and Deborah Y. Sanders, “Ameri-can Graffiti: Effects of Authority and Reactance Arousal,”Personality and Social Psychology Bulletin, Vol. 2, No. 3(1976), pp. 264–267.

31 Peter H. Reingen, “Test of a List Procedure for InducingCompliance with a Request to Donate Money,” Journal ofApplied Psychology, Vol. 67 (1982), pp. 110–118.



creates a pressure for others to be consistent withthis rule, while the latter suggests that tippinghasn’t been the norm since the fall of the BerlinWall.

Most companies have long understood theability of social validation to sway our opinionsand our wallets in their direction, which is whymarketers spend much of their time thinking ofways to spin their products as the leading, thelargest-selling, or the most popular ones out there.A common strategy is to make nebulous,lawsuit-proof claims to convey the product’spopularity among the public such as, “We’re thenumber-one cruise line in North America,” evenif not true by any reasonable statistical standard.Still others attempt to quantify their success, suchas the McDonald’s Corporation, which claims“Billions and Billions Served.”

The outcomes of social validation at work areoften the result of deliberate planning by busi-nesses to harness this principle’s power, but some-times the effects of the principle fortuitously ap-pear in unplanned and unintended domains. Forexample, some restaurants that are located insidemalls (and airports) give pagers to their patronsand encourage them to walk around while theywait for a table to become available. Since thepagers are in most cases too large to place in one’spocket, the guests usually hold them in theirhands as they stroll around the complex. Al-though clearly not intended to work in such afashion, the beepers—which are being carriedaround by a multitude of individuals—act as asignal to others that the restaurant is a popularand worthwhile place to eat a meal. This sug-gests that if a mall contains more than one eat-ing establishment with this policy, then each res-taurant would make the greatest use of theprinciple of social validation if its pagers wereboth large and distinctive enough in colors, pat-terns, or design so that a potential customer couldeasily identify the restaurant to which it belonged.

Supplying individuals with specific descriptivenorms—essentially, information about what otherpeople are doing32—to elicit comparable behav-ior has proven to be successful in a number ofdifferent domains, including neighborhoodhousehold recycling.33 Similarly, another way thathotel managers may attain greater results withtheir pleas for resource conservation is to informtheir guests that a large number of people havealready participated in the program since itsinception.

AuthorityOn the bitterly cold afternoon of January 13,1982, Air Florida Flight 90 sat on the tarmac ofNational Airport in Washington, D.C. Follow-ing a series of delays, the plane was finally clearedto take off. As the captain and the first officerwere completing their last round of pre-flightchecks, the following exchange took place regard-ing one of the systems:

First officer: God, look at that thing. Thatdon’t seem right, does it? Uh, that’s notright.

Captain: Yes it is, there’s eighty.

First officer: Naw, I don’t think that’s right.Ah, maybe it is.34

Shortly after this conversation transpired, theplane took off. Less than one minute later, Flight90 crashed into the icy waters of the PotomacRiver.

This tragedy is an example of a troubling andall-too-pervasive problem in aviation that offi-cials in the airline industry have referred to as“Captainitis.”35 This occurs when crew members

32 Robert B. Cialdini, Raymond R. Reno, and Carl A.Kallgrem, “A Focus Theory of Normative Conduct: A Theo-retical Refinement and Reevaluation of the Role of Normsin Human Behavior,” Advances in Experimental SocialPsychology, Vol. 21 (1990), pp. 201–234.

33 P. Wesley Schultz, “Changing Behavior with NormativeFeedback Interventions: A Field Experiment on CurbsideRecycling,” Basic and Applied Social Psychology, Vol. 21,No. 1 (1999), pp. 25–36.

34 www.avweb.com/articles/bogusepr/cvr.html (as viewed onMay 9, 2002).

35 Clayton M. Foushee, “Dyads at 35,000 Feet: Factors Af-fecting Group Processes and Aircraft Performance,” Ameri-can Psychologist, Vol. 39 (1984), pp. 885–893.

The principle of “social validation” asserts

that people frequently look to others for

cues on how to think, feel, and behave.



fail to correct an obvious error made by the plane’scaptain, resulting in a crash. In this case—andmany others like it—the copilot made the ca-lamitous decision to defer to the captain’s author-ity. This is a clear example of the power of theprinciple of authority; that is, we tend to deferto the counsel of authority figures and experts tohelp us decide how to behave, especially whenwe are feeling ambivalent about a decision orwhen we are in an ambiguous situation. Expertsalso have a hand in helping us decide what weshould think. For example, one study found thatwhen an acknowledged expert’s opinion on anissue was aired just once on national television,public opinion shifted in the direction of theexpert’s view by as much as 4 percent.36

Although we have seen how the principle ofauthority has the potential to steer us wrong,more often than not experts provide reliable in-formation that we use as shortcuts to make gooddecisions. In an increasingly complex world, de-ferring to individuals with highly specializedknowledge in their fields is often an essential partof smart decision making.

Some research shows that we are more swayedby experts who seem impartial than those whohave something to gain by convincing us.37 Forinstance, we tend to believe a laminated copy ofa restaurant review from a local newspaper postedin that particular restaurant’s front window orentryway because we have reason to believe thatfood critics have no vested interest in the out-come. Our confidence in a particular expertwanes, however, when we believe that he or sheis biased in some way. Although many peoplesee a “Chef ’s Choice” label next to an entrée listedon the menu as more appetizing because it iscoming from a credible authority on therestaurant’s food—the one who cooks it—a num-ber of others would be less convinced. After all,a label like this might be subject to the biasesand motivations of the restaurant managers, whocould be trying to boost the sales of a less-

popular choice or increase net earnings by choos-ing dishes with high profit margins.

Food experts. Some crafty servers are carefulto keep these principles in mind when taking theirguests’ orders. Their general approach is as fol-lows: A guest asks about or orders a particulardish from the menu, to which the food serverreplies, as if it were a secret, “I’m afraid that isnot as good [or fresh] tonight as it normally is.May I recommend instead [the names of twoslightly less-expensive dishes]?” Notice that thefood server accomplishes two important objec-tives. First, the server establishes him- or herselfas an authority regarding the quality of therestaurant’s food. Second, by suggesting two less-expensive entrées, the server seems to be makingrecommendations against the restaurant’s and hisor her own interests, since it could theoreticallylead to a smaller bill and, subsequently, to a smallertip. The server knows that, in actuality, the tipwill probably be larger because the guests willlike the server more and want to reciprocate thefavor by leaving a generous gratuity. In addition,because the server now appears to be a trustwor-thy authority on the restaurant’s food, the guestsare more likely to take any other advice offeredthroughout the course of the meal, such as sug-gestions to order expensive desserts and wine thatthey would not have ordered otherwise.

Car-rental agencies may use a derivative of thisapproach, even inadvertently, when their employ-ees offer customers extra insurance options. Inmany cases a customer won’t be completely awareof his or her own insurance policy’s car-rentalcoverage, so the rental agent makes some recom-mendations. The staff member, who is seen asthe authority on car-rental insurance, says some-thing like, “Well, you are going to have the carfor only two days, so you’d probably be wastingyour money with personal-accident insurance,the personal-effects coverage, or the supplemen-tal liability insurance. However, I would recom-mend that you get the partial damage waiver,which is what most people go for.” (Notice theadditional use of social validation.)

Knowledge of the power of the tactic used inthe above two examples goes back many centu-ries. François Duc de La Rochefoucauld, aseventeenth-century French writer and moralist,wrote, “We only confess our little faults to per-

36 Benjamin Page, Robert Y. Shapiro, and Glenn R.Dempsey, “What Moves Public Opinion?,” American Po-litical Science Review, Vol. 81 (1987), pp. 23–43.

37 Alice H. Eagly, Wendy Wood, and Shelly Chaiken,“Causal Inferences about Communicators and Their Effecton Opinion Change,” Journal of Personality and SocialPsychology, Vol. 36 (1978), pp. 424–435.



Robert B. Cialdini, Ph.D.(left), is the Regents’ Profes-sor of Psychology at ArizonaState University ([email protected]) and theauthor of Influence: Scienceand Practice (Allyn & Bacon,2001), now in its fourth edi-tion. Noah J. Goldstein

(right) earned his bachelor’sdegree from Cornell Univer-sity and is currently a doc-toral student in social psy-chology at Arizona StateUniversity ([email protected]).

38 Monroe M. Lefkowitz, Robert R. Blake, and Jane S. Mou-ton, “Status Factors in Pedestrian Violation of Traffic Sig-nals,” Journal of Abnormal Social Psychology, Vol. 51 (1955),pp. 704–706.

suade people that we have no big ones.” Manycompanies today have implemented such a strat-egy in marketing. By mentioning a shortcomingof their product, they hope to appear more hon-est and trustworthy to their potential customers,meaning that prospective consumers will assumethat the product is likely to be of high quality inall other respects. For instance, one well-knowncompany slogan is “Avis: We’re number two, butwe try harder.”

We have thus far examined the role of impar-tiality and trust in how we perceive experts andthe advice they dispense. In all of the examplesabove, those serving their customers could beconsidered—at least to some degree—legitimateauthorities. To what extent can people be ledastray by someone who is no more an authoritythan they are? A study sought to answer this ques-tion by examining the connection between per-ceived authority and the way an individual isdressed.38 The researchers had a 31-year-old manillegally cross the street on a number of differentoccasions, while they surreptitiously observed thenumber of pedestrians who followed him acrosseach time. Three times more people followed thejaywalking man into traffic and across the streetwhen he wore formal business attire than whenhe was dressed in a more casual work outfit.

Clearly, there are dangers of various kinds inher-ent in allowing non-authority figures to makedecisions for us—some of which could be poten-tially hazardous.

Some Final ConsiderationsIt is important to emphasize that although wediscussed each of the six tendencies separately forthe sake of clarity, these principles often work inconjunction with one another to produce a morepotent persuasive effect. For example, we men-tioned earlier how some sly waiters and waitressesuse their authority to gain larger tips by prevent-ing their patrons from making an ostensibly poorentrée choice. Since most customers would viewthis action as a favor done for them by an ami-cable individual, the servers also commission thepower of the liking and reciprocation principles.

Be honest. We also feel that it is imperative tostress that knowledge of the fundamental prin-ciples of social influence does not carry with itthe right to use this information unscrupulously.In trying to persuade others, one can ethicallypoint to genuine expertise, accurate social valida-tion, real similarities, truly useful favors, legiti-mate scarcity, and existing commitments. Thosewho do attempt to dupe or to trap others intocompliance are setting themselves up for a double-barreled whammy—by breaking the code of eth-ics and by risking getting caught—that can pro-duce the disagreeable consequences of diminishedself-concept and diminished future profit. �

© 2002, Cornell University; an invited paper.