ON VOCATIONAL TESTS. 271 



consisted of a fortnight's daily practice with the omission of Saturdays and Sundays 

 in the case of adults, and of a daily practice on the five school days of the week in 

 the case of school boys. 



The resulting data offer the opportunity of (i) tracing the ' reliability ' of each test 

 through the various stages of practice, (ii) investigating how the relations between 

 the several tests practised by the same group may change with practice, (iii) ascertaining 

 how the rate of improvement, as shown by the practice curves, may vary from one 

 subject to another and from one test to another, and (iv) determining how far 

 improvement in one test may ' carry over ' to another test. 



In the output records of the subject throughout his practice period there is a 

 more comprehensive measure of ' ability ' than a simple sitting is likely to yield. The 

 scores obtained at the mental tests (' general intelligence ' and ' mechanical aptitude ') 

 render possible a comparison with ' ability ' and ' improvability ' at the assembling 

 tests, and give the means of ascertaining how far these tests are dependent on mental 

 factors and how far on more purely ' motor ' factors. 



To throw light on the mental processes involved in assembling work, introspections 

 were made by the adult subjects who were supplied with a list of points upon which 

 information was especially sought. The tests were also practised by the flTiter. 



The adult subjects undertook the tests voluntarily and no special incentive was 

 offered. The general conditions at the schools were such as to lead us to believe that 

 every effort was being made by the school children to do their best at the tests. 

 Nevertheless, in case interest might flag during the practice period a monetary incentive 

 was given, based on (i) the subject's total score, (ii) the number of times the subject 

 beat his own best previous record, and (iii) the number of times his section beat a 

 rival section into which the practising group was divided. The addition of a monetary 

 and competitive incentive to those already operative establishes conditions approxi- 

 mating to those obtaining in industrial work. 



D. Data Collected. 

 Tests : Briefly enumerated, they were : 



(1) Intelligent Assembling. 



(a) Porcelain Test. In this the subject was required to assemble, without previous 

 knowledge, the various parts attached to the interior porcelain portion of an ordinary 

 electric lampholder. 



(h) Container Test. Here the metal exterior into which the above-mentioned 

 porcelain fits was required to be assembled without previous knowledge. 



(c) Wiring Test. This was done after the subject had learnt how to assemble the 

 above-mentioned parts. In it he was required to ' wire up ' the electric lampholder — 

 i.e. attach it properly to the end of a wire, the other end of which was inaccessible. 



(2) Routine Assembling. These tests employed the various parts of the lamp- 

 holder as follows — 



(a) Screw Test. The insertion of ten small screws into ten metallic blocks, with 

 the fingers, constituted one ' trial.' A ' test ' consisted of five such trials. 



(6) Porcelain Test. Assembling the parts of the porcelain interior (cf. la) of the 

 lampholder — repeated five times with adults, fifteen times with school groups. 



(c) Container Test. Assembling the parts of the container (cf. 16) — repeated five 

 times with adults, fifty with children. 



(d) Wedges Test. Assembling the two wooden wedges into the top of the lamp 

 holder — repeated five times with adidts, fiftj' times in groups of ten, with school 

 children. 



(e) Wiring Test. Wiring up the lampholder (cf. \c) — repeated five times with 

 adults, fifty with children. 



U-J) Stripping Tests. These employed the same material as the five routine 

 assembling tests : but here the subject was required to take apart the pieces previously 

 assembled, under similar and standard conditions as for assembling. 



(3) General Intelligence. All subjects took a comprehensive test of general 

 intelligence of one hour's duration, a different test being used for adults and for school 

 children respectively. 



(4) Mechanical Aptitude. The school groups took two ' mechanical ' tests, viz. 

 (a) the ' models ' type, and (6) the ' mechanical explanation ' type. A " star ' puzzle. 



