PSYCHOLOGICAL TESTS Gg 
A test which is scored in terms of the time required to 
complete a standard task is called a work limit test. A test 
which takes account of the amount of work done in a given 
time is called a time limit test. In this form a starting sig- 
nal and a stopping signal are given, and the performance is 
scored in terms of the amount accomplished (or the amount 
accomplished correctly) within the time allowed. 
In group testing only the second form is recommended, 
since it is not easy to time the individuals in a group sepa- 
rately. Some schemes have been devised for the purpose 
of adapting work limit tests to group procedure by timing 
the members of a group on a set task, or by directing the 
examinees to hand in their papers just as soon as they have 
finished, thus getting an approximate record of time used. 
These schemes are open to error and depend in part on the 
honesty of the persons tested. 
Restrictions on response. A classification of tests ac- 
cording to restrictions which the technique places on re- 
sponse is suggested by Thurstone (see below, page 96). 
TEST ITEMS 
The items of which the test is constructed should be rep- 
resentative samples of the type of behavior it is desired to 
measure. All superfluous items, all items which do not 
seem to measure just this ability, should be excluded, and 
those that are retained should furnish, as regards both 
variety and difficulty, a fair sampling of the ability or in- 
formation desired. Items which have only a temporary 
interest and are apt to become out of date should be avoided. 
A current information test soon becomes a historical test. 
All test items should be explicit and in the vocabulary of 
the men in the occupation. In each case there should be no 
doubt as to the right answer. 
Items calling for spoken responses have the disadvantage 
0s