SAMPLING

Two major

considerationsaffectthe value of the 70 adult

Rorschach

protocols, insofaras they aretobe used asdata for the elucidation of

group

personality characteristics: sampling procedures;

and admin-

istration

and

scoring procedures.

According

to thewriter's census, in July 1948 the total

number

of adult (16 years

and

older) sociological Tuscarora^{^^}

was

352,of

whom

179

were

males

and

173 were females.

The

figure 352 the writer considersto be accurate towithin about 20 persons.

The

population

was

further classified according to age. Since ages

were

in

most

casesascribed

by

one informant

(Mina

Smith),there certainly

would

be a large probability ofan error ofa

few

years

more

orlessinregard to

any

one individual. If these errors were

randomly

distributed, however,

no

consistent bias

would

affect the proportions

by

age

and

sex in

any

one age-sex

group

; if the errors were consistently plus or minus, the errors

would

be approximately evenly distributed in the age-sex categories, again not materially affecting the distribution.

The

^only serious likelihood of error

would

be in

making

consistently largemistakes with regardtoone orseveral of the age-sex categories

:

forinstance,considerablyunderestimatingtheages offemalesbetween 40

and

50, while considerably overestimating the ages of females be-

tween

20

and

30,

and

thereby (perhaps)

adding

noticeably to the

num-

ber of females ⁱⁿ the 30 to 40 age-group.

The numbers

involved in the total adult population are so small, however,

and

the absolute

numbers

in the sample itself so

much

smaller still (so small that a difference of 20 percent

from

the present count of females between 30

and

40, forinstance,

would mean

the addition or rejectionof only

^*"Sociological Tuscarora" are Indians who spent the first 6 or 7 years of their lives

onthe reservation, orwho were born and/or^raisedoff the reserve by aTuscarora mother andlaterreturned to spenda major portion of theiradult liveson the reservation. Only thoseIndianslivingonornearthe reservewereavailable forstudy.

Wallacb]

modal personality

OF

TU&CARORA

INDIANS

41

one Rorschach protocol) that the possibility of such bias does not seemtothreaten thevalidityofthesampling procedureused.

The

distribution of the population

among

the age-sex categories having been established, the writer then calculated the

number

of records necessaryto preserve the

same

proportions in the sample as

had

been observed in the population at large. These figures

were

calculated

on

the assumptionthat the sample

would

total 100 records

and

that ^it

would

include proportionate

numbers

in all age grades,

from

infancy to old age.

As

the

work

proceeded, however, it

was

decidedtoconcentrate

on

collectingaslightlylarger

number

of adults than

was

needed in the original sampling scheme,

and

the full pro- portion of preschool records

was

not filled.

A

^total of 103 records weresecured. Seventy-oneof these

came from

adults (age 16

and

up)

.

One

ofthe adult records

was

recordedonwire,witha

somewhat

differ- ent technique of administrationthan that

which was

used throughout the series; this record

was

excluded

on

the grounds that the

admin-

istrativeprocedure

would make

itnotstrictlycomparabletotheothers.

Thus

thesampleof adult records available forstudyis70. This sam- ple does not strictly follow the

form

ofthe population distribution, but the deviations are not large enough,inthe writer'sview,seriously to bias the results. Table 1 (p. 42) presents the ^{essential data.}

The

adult records thus represent a proportional sample in

which

the frequencies ofcases inthespecifiedsex-age categories are carefully controlled soas tocorrespond,in their

mutual

proportions,tothe pro- portions of those categories in the whole population.

The

selection of individuals for inclusion in the sample

was

at first left almost entirely to one of the writer's informants, a person

who had

(along with the rest of his family) taken a Rorschach,

and was

willing to introduce the ethnographer

and

^his ink-blots to possible candidates.

He would

betoldthattherecordswere neededtofillin certainsex-age categories.

He would

take the

problem

under advisement, suggest certain persons of the propercategory he thought

would

"look at the cards,"

go

withthe writerto theirhomes,introduce

him

if

he was

not

known

to them,

and

sometimes personally persuade subjects to co- operate,explaining thathe

had

takenthe test

and

giving otherneces- sary particulars. This technique

was

phenomenally successful; dur- ing the

two summers

of

work

only

two

or three persons approached in this

manner

refused totake Rorschachs.

Most

of the records

were

secured in this fashion.

As

the writer got to

know more

people, however, he

was

able in

many

cases to suggest the Rorschach and,

when

he

was

not refused, to give the test

on

his

own

presentation.

During

the second

summer,

infact,several peoplesolicited

him

tolet

them

look atthe cards

and

it

became

almost a

minor

fad, in certain circles, tohave "ProfessorWallace" drop

by

withhis ink-blots.

906418—51 4

42 BUREAU

OF

AMERICAN ETHNOLOGY

[Bull. 150

Table ^1.

—

The sampling of the Tuscarora population byage and sex

Agegroup

Wallace]

MODAL PERSONALITY

OF

TUSCARORA

INDIANS

43

cent). This difference

was

found not to be significant at the 0.01 probability level

when

tested

by

the large-sample critical ratio method. This suggests that those subjects

who

were selected

by

the informant constituted a psychological subpopulation

which was

in- distinguishable

from

the total sample,

and

hence that his selection ofcases did notbias the formulation of the

modal

personality struc- ture.

On

the other hand, however, this technique of evaluatingbias does not fully take account of the possibility that the whole sample

was

biased, because

most

(but not

by any means

all) of the writer's contacts

were

in that area of the reservation nearest to the inform- ant'shouse.

From

his personal

knowledge

of the homogeneityof the reservation, the writer does not believe that

any

significant bias

was

introduced

by

this

means

either, but he cannot demonstrate its im- probabilitystatistically.

A

cross-validation study, in

which

the sub- jects were chosen

randomly by

mechanical

means and

were propor- tionately distributed geographically aswell as

by

age

and

sex,

would

bedesirable.

The

sizeof thesampleitselfisamatter of

some moment. A

^larger

sample would, ofcourse,have beenbetterthan this; this

was

the best procurable for the time

and

money.

A

sample of 100 records is de-

manded

instandard Eorschachpractice before a statement of

what

the popular

and

original responsesare.

The

writerwillhavetogoahead to define

what

heregards as the popular responses on the basisof 70 records.

A

^sampleof70isconsidered "large" forstatisticalpurposes

and

does not require the use of small-sample theory.

From

such a small population, of352,asample of70 isreally afairly

good

size: it

includes 20 percent of the total population,

and

^since it is

known

to be proportional in several important respects, it

would

seem to be entirelyadequate.