Journal of Applied Psychology1963, Vol 47, No. 5, 300-303

SOME PERSONALITY AND BEHAVIORAL FACTORSRELATED TO BIRTH ORDER2

EWART E. SMITH AND JACQUELINE D. GOODCHILDS

Serendipity Associates, Los Angeles, California

A study was conducted using 165 firemen in large and small firehouses totest the hypothesis that first borns learn to interact more successfully becauseof their stronger dependency and affiliation needs. It was also predicted thatthis greater interactional skill would become more apparent the more complexthe social situation. As predicted, first borns had less self-confidence. Theyalso conformed more, were more efficient problem solvers in a group situation,and were more often the official leader of their work group. However, thesegroup behaviors were only related to birth order in the larger and morecomplex groups.

Schachter's (1959) synthesis of a numberof findings on the relationships between birthorder and various behaviors, and his linkageof this research with Festinger's (1954)theory of social comparison processes haveprovided us with a heuristic new theory. Thebest statement of it can be taken fromSchachter (1959):

It will be recalled that the diverse data on theeffects of birth order have all been interpreted interms of a common notion—dependence or the de-gree to which the individual relies on others assources of approval, support, help, and reference....Designating this dimension of reliance on others asdependence, it should be anticipated that first-bornand only persons would place more reliance onsocial means of evaluation than would later-bornpersons. . . . When placed in a situation someaspect of which requires evaluation, early-born in-dividuals are more likely than later-born personsto seek out others as a means of evaluation; whentogether with others in such a situation, early-bornare more likely than later-born individuals to relyon others in evaluating their own opinions andemotional states [pp. 131-132].

From these theoretical statements we canpostulate that first borns place greater reli-ance on interaction with others, as a meansof solving their problems, than they do ontheir own actions. We would therefore expectto find first borns conforming more ingroups, and would also anticipate that first

1 This work was supported by the BehavioralSciences Division, Air Force Office of ScientificResearch of the Office of Aerospace Research, underContract No. AF 49(638)-1000.

borns would have lower scores on measuresof self-reliance or self-confidence.

The greater affiliative tendencies, in timeof need, of first borns should lead to moreinteractions with others, followed by thefeedback inherent in most social interactionsituations. Consequently, one would hypothe-size that first borns would be more interestedin and experienced with social interaction,and therefore should be more successful atsuch interaction. In addition, the hypothe-sized greater interactional skills of first bornsshould be more apparent the larger and morecomplex the social situation, due to thegreater number and complexity of the inter-actions.

These considerations led us to the followinghypotheses:

1. First-born subjects will be lower thanlater borns on a personality measure ofself-confidence.

2. First-born subjects will be higher thanlater borns on:a. Conformity in their group.b. Formal rank in their group.c. Task efficiency in a group situation

under time pressure.d. Perceived clarity of the social struc-

ture of their group.3. The hypothesized relationships between

these social behavior and attainment meas-ures and birth order will be stronger inlarger, more complex groups than in smallerand simpler groups.

300

PERSONALITY AND BIRTH ORDER 301

METHOD

SubjectsThe subjects were 165 Los Angeles firemen. Ten

small single company and 10 large double companynrehouses were used. Each firehouse was visitedonce and data obtained on the entire crew present.The single company houses had one captain andaveraged S men per crew and the double companyhouses had two captains and averaged 11 men percrew. Firemen can and do transfer from one fire-house to another and it cannot be assumed that anydifferences between the men in the single and doublehouses are random.

Procedure

In an introductory statement the research wasexplained as an attempt to find out how men worktogether in groups, in order to help the govern-ment in planning crews for such special situationsas space vehicles and submarines.

The subjects first completed a questionnaire andthen worked on two problems, giving a preanswerto each problem just before the group discussionand individual postdiscussion answers afterwards.

The first group task was to discuss the followingquestion for IS minutes and to reach a groupdecision:

You are to be marooned on a desert island withno immediate hope of rescue. You are allowedto take with you three and only three thingsWhat will you choose to take?

This problem was deliberately ambiguous to providea good discussion.

The second group problem was to discuss andgive an answer within 8 minutes to the Maier (1952)Horse Trading Problem:

A man bought a horse for $60 and sold it for$70. Then he bought it back for $80 and againsold it for $90. How much money does he makein the horse business?

Measures

Self-Confidence. This was measured by the Kscale. High scores on the K scale from the MMPI(Meehl & Hathaway, 1946) are obtained by deny-ing that various negative statements (eg., "Criticismor scolding hurts me terribly") are applicable toone's self. Consequently, the K scale is a measureof a subject's own statement of his mental health,and was used as a measure of self-confidence, orwhat might more technically be termed the strengthof ego defenses (see Smith, 1959; Sweetland &Quay, 1953; Wheeler, Little, & Lehner, 1951).

Conformity. Conformity scores were obtained bycomparing individual postdiscussion answers to theDesert Island task with the answers given by thegroup. These scores could range from zero to threeaccording to how many of the three group choicesthe subjects utilized.

TABLE 1

MEAN CONFORMITY AND ROLE CLARITY BY

BIRTH ORDER AND GROUP TYPE

Type

Large groups

First bornLater bornt

Small groups

First bornLater born/

A7

4163

2326

Meanconformity

2.542.182.33'

2.562.311.10

Meanrole clarity

94.3488.38

2 30*

92.3593.420.26

*P 05.

Perceived Clarity of Group Role Structure. Thiswas measured by an 18-item Likert-type RoleClarity scale designed to indicate how clear thegroup role structure appeared to each subject.Typical items are. "We know what to expect ofeach other in this group," "I understand the peoplein this group," and (scoring reversed) "It's hardto guess how we'd act in an emergency."

Formal Rank. Information as to whether eachsubject was an ordinary fireman or a fire captainwas obtained.

Task Efficiency in a Croup Situation. This measurewas each individual's post-group-discussion answerto the Horse Problem, scored correct or incorrectIndividual prediscussion answers were also obtained.

R E S U L T S :

The data on the behavioral measures wereanalyzed separately for large and smallgroups. Only-born subjects were alwaysclassified as first borns.

On the K scale the 70 first borns had amean of 16.49 compared to 17.98 for the 95later borns, with a t of 2.45 (p < .05).

The results on the conformity measurewere consistent with previous research(Schachter, 1959) with first borns conform-ing more than later borns in large groups,as shown in Table 1, with a t of 2.33(p < .05). However, the differences in thesmall groups, while in the same direction,were not significant.

2 The N is 153 on some measures, as 12 subjects,8 from the large groups and 4 from the small, werenot present for the two group tasks. All statisticaltests are two-tailed.

302 EWART E. SMITH AND JACQUELINE D. GOODCHILDS

TABLE 2

STATUS AND TASK EFFICIENCY BYBIRTH ORDER AND GROUP TYPE

Type

Large groups

First bornLater bomXJ

Small groups

First bornLater born

Formalrank

Cap- Fire-tain men

12 347 594.61*

4 205 24

Horsetradingproblem

Cor- Incor-rect rect

32 936 27

4.80*

18 517 9

•p <.0S.

The first borns also scored higher on theRole Clarity scale, in the large groups, witha t of 2.30 (p < .05). There were no signifi-cant differences in the small groups, as canbe seen in Table 1.

First borns were more frequently captainsin the large groups than were later borns,as shown in Table 2, with a chi square of4.61 (p < .05). There was no difference inthe small groups.

The first borns also scored higher on theHorse Problem, as shown in Table 2, butagain the difference was only significant inthe large groups (x2 = 4.80, p < .05). It isinteresting to note that the first borns werenot superior to the later borns on the HorseProblem prior to the group discussion, indi-cating that the first borns benefited morefrom the group discussion than did theothers.3

DISCUSSION

Our findings appear to support and extendthe theorizing of Schachter (1959). Of par-

3 A more parsimonious explanation of the HorseTrading Problem data might be that this is con-formity behavior, similar to that on the more am-biguous Desert Island Problem, as most of thegroups, 14 out of 20, gave the correct answer tothe Horse Problem. However, separate analyses ofthe data on the correct and incorrect groupsrevealed that the first borns conformed significantlyto the group answers in the former but not in thelatter.

ticular importance are the data on the Kscale, in view of the previous lack of birthorder differences on personality tests. Ourinterpretation of the K scale (on normals),as a measure of self-confidence, and the lowerK scale scores of first borns supportsSchachter's (1959) and Sears' (1950) de-scription of first borns as more dependent.

The first born's reduced self-confidenceand hence greater dependency on others ap-parently produces the greater conformity seenin our data as well as Schachter's (1959).The results on the measure of perceivedclarity of the group role structure are anotherindication of this greater dependency on andinterest in interpersonal relations.

The superiority of the first borns in thelarge groups on the Horse Problem, which hasa correct answer, is particularly illuminatingin the light of the results on the conformitymeasure on the ambiguous Desert Islandtask. The first borns were not correct morefrequently than the others on the HorseProblem before the group discussion, andwere only more superior in those groupswhich solved the problem. And it was onlyin these latter groups that the first bornsconformed to the group solution. Theseresults indicate that first borns not only seekout and respond to others more frequently,particularly under stress, as demonstrated bySchachter (1959), but they also seem toprofit more from the association. Conformitytendencies are not so strong where there isa reality factor that first borns disregardcorrectness. Hence we should not think ofthe apparent dependency of first borns in anegative manner, although dependency hassuch a connotation in our culture. This seekingout of others for help seems to be functional.And it may have been this responsivenessto the thoughts and feelings of others thatresulted in more first borns attaining the rankof captain in the large, complex firehouses.This finding may be related to Schachter's(1959, p. 78) observation that first-bornstudents belonged to more organizations thandid later borns. However, it must be notedthat we do not know what mediated birthorder and attaining formal leadership in thelarge groups. Perhaps further exploration of

PERSONALITY AND BERTH ORDER 303

the psychology of the first born will leadto successful attacks on the problem ofleadership, a problem swept under the rugyears ago.

It must be noted that the behavioral rela-tionships found held only in the large, morecomplex firehouses. This strengthens ourtheoretical assumptions that the relationshipsbetween birth order and the behaviors andattainments investigated are mediated by agreater responsiveness to others and abilityto interact successfully, and also suggestsfuture areas of research, such as family size,for increasing our understanding of birthorder psychology.

REFERENCES

FESTDJGER, L. A theory of social comparison proc-esses. Hum. Relat., 1954, 7, 117-140.

MAIER, N. R. F., & SOLEM, A. R. The contributionof a discussion leader to the quality of groupthinking: The effective use of minority opinions.Hum. Relat., 1952, 5, 277-288.

MEEHI., P. E., & HATHAWAY, S. R The K factor asa suppressor variable on the Minnesota Multi-phasic Personality Inventory. / . appl. Psychol.,1946, 30, 525-564.

SCHACHTER, S. The psychology of affiliation. Stan-ford: Stanford Univer. Press, 1959.

SEARS, R. R. Ordinal position in the family as apsychological variable. Atner. sociol. Rev., 1950,IS, 397-401.

SMITH, E. E. Defensiveness, insight, and the K scale./ . consult. Psychol., 1959, 23, 275-277.

SWEETLAND, A., & QUAY, H. A note on the K scaleof the Minnesota Multiphasic Personality Inven-tory. J. consult. Psychol, 1953, 17, 314-316.

WHEEIER, W. M., LITTLE, K. B., & LEHNER, G. F. J.The internal structure of the MMPI. / . consult.Psychol, 1951, 15, 134-141.

(Received August 23, 1962)