validity of pretests

8/4/2019 Validity of Pretests

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DC 132

Handout 3

Fac tors Affec ting the Valid ity o f Pretests

Sub jec ts Samp led Sett ing for Prete st Ma nipulat ion Measurement

rand om sam ple of

the potential

audience

the same sett ing a s the

one in whic h the aud ienc e

will see the fina l

production

present the finished

prod uc tion a s it w ill

ultimate ly be

presented

intended effect

of the prod uction

persons different from

the intende d

audience

restric ted und isturbed

setting

present a fac simile

or moc k-up o f the

communication

som e c riterion

othe r than the

intended effect

Theo retical Approac hes to the Process of Pretesting

1. Holistic Approa ch

• Found ed in the theories of Gesta lt psycho logy which views be havior in the total context of

a situation.

• The individua l rea c ts to the tota l situation rather than to single eleme nts of it. Thus, an

individua l might rea c t to a violent story different ly if tha t story oc curs within the c ontext of a

reg ular religious service tha n if it is presented to h im at a d inner tab le.

• It would b e impossible to p red ic t an individua l's rea c tion to a stimulus outside a lab oratory,

if we only knew how he ha d rea c ted to tha t stimulus within a labo rato ry situat ion.

• One should pretest in a setting w hich is as c lose as possible to the one in which the

audienc e will finally expe rienc e the communica tion.

2. Atom istic Approach

• Most c losely linked to the wo rk of the behaviorists.

• Individua ls rec ognize and rea c t to pa rticular elements in the environment. Eac h element

in the e nvironm ent has stimulus va lue for the ind ividua l.

• It is possible to measure the effec t of any stimulus on an individua l.

• Prete st results ob ta ined in the restric ted sett ing of the laboratory or other "artific ial

situations" can be valid and ca n b e used to p red ict the a udience's reac tion to the

communication.

Should the pretest be adm inistered to ind ividua ls or groups?

1. Group interview can be useful if:



2

• One is pretesting conc ep ts or ide as for a communica tion program rathe r than almost

finished productions; useful in providing feedback early in the creative process.

• If there are known c ircumstances tha t will ma ke individua l prete sting difficult, e.g., in

p retesting a short film on c hild c are, it would b e m uch ea sier to show the m ovie to a group

of wo men in a central plac e than to g ive a n individua l showing to each one since there

ma y be no elec tric ity in the homes.

2. One-to-one allows the p retester to obta in a num be r of indep end ent op inions regarding the

message or ma terial being tested .

Should the questionnaires be self-administered o r should an interviewer be used?

Self-administered questionna ires a re no t recomm ended in deve loping c ountries since:

1. Results will have little valid ity if the ta rge t aud ience had d ifficulty rea d ing and writing.

2. Respond ents will tend to skip over items which lea ves the prete ster with incomp lete da ta .

3. Respo nde nts ma y go b ac k and change their answers to ea rlier questions afte r rea ding

other item s on the questionna ire.

By cont rast, the interview er is ab le to obta in spontaneous rea c tions that a re not b iased by

que stions which ap pe ar late r on the form.

Method s of Ob taining Information from Pretest Subjec ts

1. Direc t Que stioning.

• Effectiveness of direc t questioning in pretesting dep end s hea vily upo n the skill of the

interviewer and the charac teristics of the subjec t .

Advantages of direct questioning method

• subjec t does not have to be de ceived ab out the purpo ses for which the questions are

being asked.

• interviewer can probe for information about the mate rial or the setting which were

pa rticularly imp ortant fo r the subjec t.

2. Inte rpersonal Simulation.

• Psychiatrists argue tha t ind ividua ls ofte n attribute em ot ions, mo tives, and intent ions to

others which the y them selves hold .

• In princ iple then, individua ls can express more easily the ir ow n fee lings and ideas whenthey a ttribute them to o thers than when they p resent tho se ideas as their own.

• The experimenter asks the subjec t spe c ific questions ab out what one of the subjec t's

friends wo uld do if the friend we re to p articipate in the experiment . The subjec t is free to

validity of pretests

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