CA1054363A - Persistence test apparatus - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
A mounting and control arrangement is provided for a threaded rod such that a subject spinning split nut on the threaded rod can be "timed"
for successive trial rotations. One series of times are taken with the threaded rod stationary. One or more trial times are taken with the threaded rod being rotated at a speed that requires more concentration and effort on the part of the subject. The various time trials are assimilated to provide a "persistence" rating for the subject.

Description

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Indicative oE prior art apparatus are the following U.S. patents:
The toy disclosed by Britt (No. 2,920~418, issued January 12, 1960) has one, or more, matingly threaded units; the re-assembly unit of Barnabas (No. 3,276,149, issued October 4, 1966) discloses the use of indicia in connection with the re-assenbly; the Leitner patent (No. 3,388,630, issued June 18, 1968) discloses both methods and apparatus for ascertaining a viewer's interest;
and, the Harrison patent (No~ 3,747,589, issued July 24, 1973) discloses various sensory reaction times for a given subject.
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Among the objects and advantages of my invention ~-are the following;
~ . , (1) To provide an aasy-to-assemble and relatively inexpensive device for presenting a plurality of tasks of success-i~7ely increasing difficulty to a given subject.

(2) To provide means for varying the use of the ,~! , device to acco~unodate either left-handed or right-handed subjects.

(3) To provide means for varying the rate at ~hich different subjects complete the tasksr yet provide simply evalu-.. . .
- 20 ated results which are convertible to data that will still make the individual results comparable to a "norm" for a random group of subjects.

(4) To provide a structure that is readily mani-pulated by both an Examiner or observer, and a variety of subjects having widely varyiny motor capabilities.
(5~ Provides a flexible research tool in work evaluation training programs to assess such key factors as a - person's c:urrent potential for work and industry, as evidenced by his average rate of work, his degree of pPrsistence, and his general level of productivity. Specialize-l research programs could be set up to measure his work tolerance, fatigue, and frustration levels. Ln subsequent work adjustment training ~, .
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., ~0~363 programs, it provides a valuable research tool in which to monitor progress made in the foregoing areas.
The present invention i5 defined as an apparatus for testing the persistence of an individual subject including a threaded rod, nut means moveable along a fixed portion of the length of the rod, the portion of rod being limited by standards supporting the rod! power means connected to one end of the threaded rod, means for controlling the speed and direction of rotation of the threaded rod, a tachometer connected to the end of the threaded rod opposite to the power ~ .
means, and means connected to the nut means for varying the force necessary to move the nut means along the threaded rod.
Figure 1 is a side view of my structure with some ~`
parts schematically shown.
Figure 2 is a cross-sectional view, of parts o~
the device enlarged and taken approximately along the line 2-2 of Figure 1. -Figure 3 is an enlarged cross-sectional view o~ the nut means and . ~, ~ , .

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related structure, taken appro~im~tely ~Long the llne 3-3 of Flgure 2.
Figure 4 i8 a similarly enlarged cro3s-sectional view taken approxi-mately along the line 4-4 of Figure 3 showing the tapered ends of the pins of the inner nut means seated in the notched~out portion~ of the outer nut means.
Figure S i~ an exploded view of a single ~et of one of the pin-spring-sleeve combination~.
Flgure 6 is an obverse view of the smaller halE of the split nut, as viewed in Figure 2, wlth other parts removed. ;~
A base member 10 suppor~s all of the various constituents of my 10 apparatus. Threaded rod 12 i9 clear o ob~tructlons for the major part of itsextent. Rod 12 is supported by standards 14-14 which rotatably receive rod 12, and which in turn are ~upported by 10. Rotary power source 16 (preferably ^ electric) is flexibly coupled, at 18, to rod 12. A similar flexible coupling member 18 i3 used at the oppo~ite end of rod 12 to carry the rotation of rod ' 12 to tachometer 20.
7 A control panel 22, ~ecured ko base 10~ carries controls for motor ;~
16. In par~icular, reference charac~er ~4 deno~es a safety fuse; 26 repre~
sents an on-off switch; 28, an indicia-bearing dial to record the approximate rpm of the output ~haft 30 of ~o~or 16. Nember 32 represents a clockwise-20 rotation, neutral, and counterclockwise-ro~atlon control mPans, all such portions of the control panel 22 being ~uitably connected to the motor 16 by ~uitable wiring, etc. shown schematically at 60.
The ~plit nut means is generally indica~ed at 34, with the left-hand (a8 ~ewed in Figure 1) larger part denoted by 36, and the smaller part by 38. 36 and 38 are each centrally threaded to recelve threaded rod 12. An Allen-type bol~ 40 passes through an arcuately-shaped aperture 37 (flanged at 39 to receive the hesd o~ 40j, and bolt 40 is threaded into 36 (Figures 2, 3 and6) in the threaded aperture 42. This design oi 36, 37, 38, 39, and 40 allows a constant and reproducible br~king force with very little maintenance or 30 serYicing required.
Reference numeral 44-44 indicat:e generally the pin-spring-~lee~e combination~ of my device. They are preferably three in number, and each spaced 120 irom the other in smooth radial bores in 36. Using Figure 5, one i. . . .

~S~ 3 of the 44 combinations in thls exploded view shows a generally hollowed-out cylinder 46, preferably of 3ta~nless steel, with a conically-shaped nose 48 at its closed end. A bottom hollowed-out cylinder 50, preferably made of nylon, or similar plastic n~terial and deformable, has an arcuately-shaped bottom wall 52 which ma~es with the outside diameter curvature of rod 12.

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Springs 54-54 are received in each of the paired hollowed-out cylinders 46 and 50. The inner periphery of thak portion of 38 that overlaps 36 has three V-notches, or coniGal depre~sions, 56-56,whlch recei~e nose portlons 48-48, in ,;~
one position of use.
When 40 is "loose", 36 and 38 may be manually rotated, approximately 40, with respect to each other. When 46 and 56 are matingly seated, 3pring 54 i5 substantially "relaxed", and thus li~tle or no pre3sure is applied to rod 12 via the bottoms 52-52. ~owever, when 36 and 38 are rotated with respe~t to each other, 46 46 are forced out of depressions 56-56, thus com-pressing springs 54-54. When 40 is tightened, and 54-54 are under compression, ':
they will iorce 52-52 into pressured engagement with rod 12, r~king rod 12, - with the associated nut means 34 thereon, more di~ficult for ~he subject to turn on rod 12, even with the ~lightly knurled ou~er sur~aces 58-58 on 36 and ... .
38. 62 is a braking washer used during the initial s~ationary-rod and hand-spinning the nut mean~ "runs".
Before going in~o further a~pec~s of i~fi operation and use, the following is given by way of background regarding my device, and ~he way it i9 intended to be used.
Abbrevi~tions used: S - subject; PTA ~ persistence te~t apparatus, STA = Statior~ry tirne average; RT ~ rotating trial; TRT - total tirne spent in rotsting trials; and MR = ~otivation~l rating.) A person's degree of rnotivation for work and industry i8 an inherent personality ch~racteristic which varies widely from person to per~on, and is the result of a ~et of n~nerous complex variables that developed durlng growth and development of the individual'~ personality.
Of all the variable~ which he]p determine a per~on'~ work motiva-tion, one of the mos~ valid indices of motivation to be productlve is the degree of persistence one posses~es~ This psychological trait, which every 11)Si~3~3 individual pos~esses in varying degrees, is psychologically defined as "m~in-taining a course of actiDn despite obs~acles or opposition." Persistence can ~lso be thought of as "~ native capacity for ~ork or energy release1'. The measurement of an individual's degree of persi~tence is achieved by i~olati~g the most com~on fsctors of the trait and then devising an objective method of measuring these individual factors.
Most researchers have consldered "withstanding discomfort to achieve a goal" and "keeping on at a task to achleve a goal, or plodding" to be the ~ two most important factor~. There i8 enother factor which seem~ to be inher-- 10 ently associated with persistence, which I h~ve found in my own research efforts into persistence to be extremely lmportant, and that is "constancy of effort in perEo-~ance of a task".
A preci~ion AC solid s~ate motor speed control unit i~ used which accu-rately varies the rpm of the fractional hp motor from 30 rpm through approxi-mately 2000 rpm.
With 8 inches of travel, the fas~e~t possible time to spin the nut from the left standard or pillow block 14 to the r~ght s~andard or pillow block 14 would be under 10 second~. The slowest possible time would be some minutes, but in nearly all c~sea it would not be expected to be more ~han five 20 (5) minuteæ. With 20 turns to the inch (SAE 20 fine thre~d), with 8 inches of ~; ~ravel, ~his would give 160 turns (revolutions) for the nut's travel along the `~ rod. Therefore for a theoretical extreme upper limit o 6 second~l the equiva-lent rpm would be 1600 rpm.

revolutions - rpm time in minutes 160 rev. 60 sec. 1 , 1600 rprn min 6 ~ec 160 rev. 60 ec. 1 _ ~ 30 rpm mln 320 sec The extreme theoretical lower limit would be approximstely 320 sec. and ~he equivalent rpm would be 30 rpm.

The heaviness of the knurl on the nut is an important consideration.
The knurl shou~d be light, ~ust enough to prevent slippage of the fingers when light to derate finger pressure i8 exerted on the nut. Too heavy a knurl ' .
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~63~i~363 would ~ause ~he nut to be spun with on]y minor phy31ral effort. The knurl should be heavy enough so that a person mu~ apply a steady even pressure of his fingers against the nut in order to spin the nut along the shaft. If too ; light a finger pre3sure is used~ a good grip cannot be maintained (sllppage will occur), and therefore, the nut will not spin as fast. Consequently, a person's time vf completion of ~pinning the nut will be less than on another trial in which he applied more CQn~tant effort and finger pressure. This vari-abllity of efEor~ from one trial to the next can be easily mea3ured by compar-ing the times.
10In the first part of the test, a S iE simply asked to ~pin a large .~
nut from the side of the left pillow block 14 to the side of the right pillo~
block on the word "go". This involves using his preferred hand and manually i turning over (spinning) the nut anti-clockwlse (~ounter-clockwise~ along the stationary threaded shaft with the braking washer jamming the shaft so that it cannot turn. The time required to move the nut from the left hand pillow blo~k to the right one is recorded on a stop watch. Four trials in this manner are given to the individual being ~ested. Then a time average called the Station-ary Trial ~verage (STA) i8 calculated from these four ~imes. This figure in seconds can be thought of as a good representation of his average time rate of doing a simple motor ~ask, and realistically assesses how 810w or how quick-ly his average rate of work i~. This knowledge i9 very i~portant in work evaluation programs and is especially useful in work adjustment training pro-graMs to assess ~raining eforts designed to increa~e one's rate of work and productivity.
The second important result of the fir~t part o~ ths test is the measurement o~ the factor o a person's variability in periormance at the spinning task - that is, how cons~ant wa5 he in "persisting" on ~he ta~k. A~
described, the primary functlon o 44 in the nut means is to provide a braklng ~orce which will decrease the nut'~ momentum, ao that when a per30n's hand is not ~ctually in phyaical contact wLth the nut, the resistance ~orce will 910w down the forward ~pin of the nut, and thereby accentuate the periods of time when a person does not consistently apply a steady, even, rhythmic stroke on ithe nut; or momentarily slougha of at ~he job or hesitates. This time "o~f :
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. , , ~5~;363 the ~ask" will be revealed by ~ longer trial time than on a sub~equent trial in which he is m~re diligent and constant. A corollary function of ~he nut means i~ to present a work task which requires a signif~cant expenditure of ~; enargy and which i8 not too easily performed.
;~ The range is the si~plest to use, and is simply the longest minus the shortest trial time of the four trials. For e~ample, if 10 seconds was the longest time trial and 6 seconds was the shortest, the range would equal 4 seconds. This would reflect the variability of work perfor~ance of the task, and give a quantitative measure of the person's constancy of effort. This factor is a vi~al ingredient of work perform2nce, and 1~ impor~ant in monitor-ing progress in work adjustment training programs.
In the second part of the test, the rotating trials portion (RT~, the factors in persistence of "withstanding discomfort to achieve a goal" and "keeping on at a task to achieve a goal (plodding)" are incorporated.
In the first part of the test, one of the work traits measured was an individual's average rate of work, represented by his statio~ary time average (STA~ for four trials. If an individual is asked to perform a motor task, such ~` as required on the PTA, and accomplishes the task with a certain rate of work, and then is asked to perform the same ta~k under more "discomforting" or "di~-ficult" circumstanGe3, his perEistence to continue to work or even work harder at the task is shown by his perserverance.
This factor of additional "discomfort" or "difficulty" i8 created by setting the motor speed control to the rpm which is equivalent to the S's ~ ;
~- average rate o~ spinning the nut during the first part of the tes~. Tha~ is, the ~hreaded shaft i8 rotated backwards at a ~peed equivalent to the ~8 natural Porward rate of spin, 30 that in order to move the nut forward along the shat the S must exert more effort to ~pin the nut, since the threaded shaPt retards the Porward motion of the nut continuously. In es~ence, the S
must work harder than before and "persevere" to accompli~h the goal of gettiag - 30 the nut to the other end of the threaded ~haft.
The second m~ln factor in persistence, "keeping on at a task to achieve a goal" is measured simply by the number of RT trials the S accol~plishes before he "gives up" and declines to try any more RT. The greater the number :, - .................................. . . .

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~6~543~;3 of RT completed, the greater the degree of persi~tence shown. Also indicative of this factor i9 the total tima that a S spends in doing the number o rotatlng trials he accomplishes before "quitting", known aa the total rotating time (TRT), that i8, th~ su~ of all the rotating trial t~mes.
Test Instructions and Procedures A. Instructlons: 1. First part of test; Stationary trials.
"This is a test to see how well you can use your hands. The object of the test ls to spin the knob (nut~ from the left ~ide of the threaded rod to the right slde of the word 'go'. YGU ~Nst place your non-pre2rred hand behind your back thro~ghout the testing; you can only use your preEerred hand ~left or rightj to spin the knob (nut). You will be given one practice trial before the actual test begins. Do you have any que~tions?"
2. Second part of test; Rotating trial~
"On this porti~n of the test you are to try to move the knob ~ ~
along the shaft from left to right while the shaft i8 turning against you. ~;
You may have to work harder than beEore when the shaft was stationary, but it i~ possible to do ~hç task. Would you like to have a few trie~ at doing this?"
After completion of the firæt RT, the S may ask lf he ha~ to do another one3 or he may just ask to go on to the second RT. When the S asks how many ~rials IA20 he is expected to do, the examiner answers, "As many as you wish - when you don't want eo do any more trials, just tell me." When ~he S, for in~tance, does five RT and then says that he doesn't want to do any more trialR, the test i3 completed.
B. Procedure: ' The testlng procedure of the PTA is a vi~al part in the actual m~surement of persi~tence, and i8 closely associated with the electro-mechanical de~ign sf the apparatu0 itselE.
In order to au&ment the factor oi physical discomfort of a S
taking the te~t and also increa~e the difficulty inherent in the perfor~ance of spinnj.ng the nut fr~m leit to right along the sha~t, ~he S iæ asked to p'lace his non-preferred arm and hand behind hi~ back, and maintain it in that posi- ~ ;
tion throughout the testing period.

The S is asked to take the te~t standing up, with the PTA placed ~ . , ~5~3i~3 near the edgP of a standard height de~k or t~ble. The e~aminer i8 ~ated - across the table and operstes the motor speed control, reads the tachometer, records the time of the trials, change~ the shaft from non-rotating to rotating,and records the data of th~ tes~. In order to measure the difficulty and dis-comfort which is inherent in the per~ormance of spinning the nut from left to ; right along the shaft, the S i~ asked to place hi~ non-preferred arm and hand behind his back and hold it there ~hroughout the testing period. With the preferred hand he spins or ~urns the nut from the left pillow block to the Y ri8ht one on a com~and to go. One complete trial consi~ts of rotating the knob from the left pillow block to the right one, and the examiner records the time ~` in seconds with a ~top wstch.
At the end of the four stationary trials, the S i3 glven a few ~-minutes rest, while the examiner calculate~ his average time rate of turning ; ~he nut on the four trials. From precalculated tables, the motor speed control i8 set at the rpm which repre~ents his average rate of turning the nut on the four trial3. The motor i5 set to rotate clockwise when switched on. The motor ;`
is turned on, and on the command "go" the S spins the knob from left to right ~'r along the spinning shaft This mark~ the beginning of the RT trials portion of -l the test.
Y 20 After completion of each RT the examiner records the time taken to do the trial and the number of the trisl.
It i8 very impor~ant that the examiner do¢~ not give the S any un-neces3ary encouragement to do more trials than he migh~ do without encouragement.
Com~ents such as "~ell, why don't you sry Ju~t one more" are con~rary to the purpose oE a test of per~lstence. The S i8 ~imply told ~hat he may do as msny trials as he wishe3 sfter ~he firat one, and can quit when he ieels he has done enough trial~. The number of RT is the number of trials success~ully comple~ed ~;
before stopping. The S must comple~e at least one RT for the test to be scored.
Scoring of the PTA
One of the most widely used methods of understanding the relation-ships betweenpsychological variables i~ ~ ~tati~tical technique known as cor-relation. In popul~r u~age, correlation refers to any type ol rela~ionship bet~een objects or events. In statlstical analysis, however, correlation refers :

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"'~, ' , ,'' ' , , ~6~S~3363 exclu~ively to a rela~ion~hip between two v3rlables that can be qusntified or ~ objectively measured. There muBt always be at least a numerical measurs for ; ea~h 3ubject to yield a correlation.
For instance, to take an example ~rom education, we would like to know if and how academic performance in college can be predicted from high school grades. In order to discover ~hat kind oi relationship may exist between college 6uccess and high school performance, we would compare high school and college grades of a randomly chosen sa~ple of ~tudents. U~ing the students' grade point average, we would calculate a coefficient of correlation from an algebraic equation using the studen~s' high ~chool and college CPAs as the t~o measures being correlated. This coe~icient, "r", then e~pre~se~ ~he degree oi relation~hip between performance in high 3chool and in college. Mathematic-ally, 'Ir" can range from +1.00 to -1.00, with ~1.00 indicating a perfect positive relationship, and -1.00 indica~ing a perfect negative relationship~
An 'Ir'9 - 0 reflec~s no relationship at all. The ~ sign of an "r" means that j individuals who ~core high (or low) on one measure tend to score si~ilarly on i. .~ .
~ e other measure as well. If "r'l is negative, thi~ means ~hat an individual `,;! who scores high on one mea~ure tends to score low on the other.
` There is ano~her statistic~l technique that i3 widely used in -~ 20 psychological research and i3 ~imply an exten~ion of "r" to more th~n two vari-ables. This technique i~ called multiple correlstlon, and is the relation~hip between one variable (Y) and ~wo or more variables, such aq Xl and X2, con-sidered si~ulta~eously.
Still another widely used ~tatis~ical technique i9 a~sessing the relationship between one variable and one or re other variables con~idered together, and is known a~ regression. This ~echnique is clo~ely relatet to ~ultiple correlation, which tells us generally what degree o~ relationship exists between two or more variables. ~l8 there a relationship, ho~ close 19 lt, and is i~ po~i~ive or negative7) But regres~ion goe~ one step further and tells U2 whst "purticular" relationship e~ists between a ~ingle individual'~
score on one ~easure and his scor~ on another measure. In the case of the previou~ly cited example of high school grAdes versus college GPA's, regre3sion ; would permit u~ to make a prediction regardlng an indivldual college student's _g_ ;
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~L~543f;3 predic~ed GPA based on his hi8h school GP~.
The variable whlch we are m kin8 the prediction from i~ known a~
the predictor variable, and the variable which is predicted i8 called the cri-ter10n variable. For example, using these two variab7es, the criterion vsriable would be the college grade point average (GPA) and the predictor variable is the student's high school GPA.
The general statistical schema outlined above is utilized to ~core the PTA. To begin with, the criterion variable is ~imply a person's overall motivation for work, as evidenced by his persi~tence. Thi8 can be quantified in several ways, but one of the si~ples~ would be the scale shown below, with motivation rated on a sGale of 1 to 10, from very low motivatlon ~o very high motivation ~o w~rk. Such a scale would be used by a worker's supervi~or to -1 i ,A~ obtain a subjective evaluation of a per~on's motivation for work. ;~;

M~tivationa~ L~3 ~, Extremely motivated for work 10 ~, Very highly motivated for work 9 Highly tivated for work 8 ;, ~ -~oderately motivated for work ~ 7 Slightly motivated for work 6 20 Slightly unmotiva~ed for work 5 :-Moderately unmo~ivated for work 4 ~ ~ighly un~otivated for work 3 ;' Very higbly unmotivated for work 2 Extre~ely unmotivated ~or work That i~, a person achieving a 3core of 8 would be considered highly motivsted fo~ work (MR ~ 8). This then is the variable we wan~ to predict, the criterion vari2ble (MR). To do this we must have s~me predictor variables, to `~
i predict one'a level of motivation. In the PT~, these predictor varisble3 are used: the number of rotating trial~ sccomplished (~T), the total time spent in the rotsting trlals portion o~ the te~t (TRT), and the degree of variability shown during the stationary trials portion of the test, range or standard devi-ation, (STVar). To ~ummsrize, there are three variables u~ed to predict the ~ ;

criterion variable, mo~ivational rating, and these predic~or variables are RT, TRT, and variability oi ST.
To take a hypothetical example, let U8 suppose a smsl1 ~ample of100 factory workers have taken the P~A snd have been ~ub~ectively rated on by management. ~le are intereated in using the PT~ data derived from this ~ ~.

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~5~3~ii3 : 3ample to predict ~ new f~ctory applicant's MR ba~ed on hi~ scores on STVar, RT, and TRT. From each of the 100 worker~ we have their ~cores on each of the 3 predictor variables. In order to ascertain the d~gree of validity these predictor vAriables po~ses~ in the sample, we calculat~ coafficients of cor-relation with ~R using the predictur variables scorea, and this, for example yields the following resul~s:
' Coefficients of Correlation "r"
Criterion vari~ble Predic~or variables MR STvar RTTRT
. 10 r rl r2 r3 . . .
: where rl, r2, and r3 are actusl numerical value~. Using the~e individusl r's of rl, r2, and r3, we then can calculate a "R" or coefficient of multiple cor-., .
relation of three variables (~123~.

Let us say for illustrative purpoæes that rom the 100 workers' data :. :
~ an ~123 of .60 wa~ yielded. Such an R123 = .60 would probably i~dicate a i~ moderately high degree of rela~ionship of the three predictor var~ables ~T~ar, ` RT and TRT when they were considered a9 operating "collectively or together"
to predict ~R. If this R123 - .60 was stati~ticaliy signiflcant for this sample, t~en this coefficient can also be known a~ a coefficient of predictive .
validity. In most py~chological and educational circles a coefficient oi predictive validity as low as .45 is considerPd by m~ny to be the lowest ~ -predictive validity coefficient for a test of practical u~efulness.
.~ Once we ha~e determined the predictive validity of the predictor v~riable~ u~ing multiplé correlation, we can then eel eonfident if it i9 high enough, to u~e the multiple regression technique using the 100 factory workers' individual scores on STV~r, RT, and TRT, and MR to predict a new 3~
applicsnt's MR score based on his STVar, RT and TRT scores. The multiple regression equation for three variable~ is given by:

~ y = a ~ blXl ~ b2X2 ~ b3X3 (1) :i 30 where Y ~8 the criterion variable (predicted ~R ~core of the ne~ applicant), a i9 a constantS bl, b2, and b3 are regr0s~ion coefPicients for e~ch of the , 1 .
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1~5~ 3 predic~or varlables, and Xl~ X2, and X3 are the predictor varlablc them3elve~
(Xl ~ STVar score, X2 = RT score, X3 = TRT score).
In order to sub~titute a new factory applicant's scores on Xl~ X2~
and X3 into the equatlon to yield a value o~ Y, the predicted MR for him, we need to compute the values of a, bl, b2, flnd b3 fro~ ~he data of the sample of 100 factory workers, where the ~1~ X2, and X3 are known for each worker, and the Y was sub~ectively evaluated by managemsnt, also for each worker. This i8 accomplished by solving the following set of simultaneou~ linear equations, which will y ld values of a, bl, b2, and b3.

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~X1Y ~ bl~Kl + b2~xlx2 -~ b3~XlX3 ~ a~Xl ~X2Y ~ bl~XlX2 ~ b2~X2 + b3~X2X3 ~ a~X2 (2 ~3Y 5 bl~lX3 ~ b2~X2X3 ~ b3~,X32 + a~'X3 ~Y ~ bl~l ~ b2~X2 + b3~X3 ~ an where ~ means "the total sum of", and n i8 the number in the sa~ple.

'~,! Onc~ values of bl, b2, b39 and a are determined from these equations, they are subs~ituted into equation (1~ Y = a ~ blXl + b2X2 ~ b3X3. Then for individual scores of a new applicant on the Xl, X2, and X3 scores, a predicted Y (~otivational Rating) is given~ That is, using this regrassion sample, a new factory applicant's MR score could be predicted using the regression sample dsta which gave a, bl, b2, and b3, and the applicant~a Xl, X2 and X3 scores ob~ained from the PTA.
The above schema requires that the PTA be given to an initial sample of indivlduals before a given per60n can be scored on the level of motlvation for work that he poxsesses. A~ ~he PTA comes into use, the ~est results ~rom much larger and varied groups will become available, and these regression sample~ will become the established norms to predict ~R for many different groups of people. ~ventually norms can be established for factory workers, student3, busine~smen, etc. coverin~ a wide variety of occupations, a~ well as norms for ~he general population.
In a givzn te~t run on an individual subject, operation would be a~
follows, after giving the neces~ary instructions to the sub~ect.
With the brake means 62 set to keep rod 12 stationary, the ob3erver , ... .
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~354363 runs 34 to one ~ide or the other, depending upon the preference of the individual sub~ert. The sub3ect make~ hls four timad "runs" with the rod 12 ; stationary. Taking the lowest (fastest) time, or ~he average time, depending upon how the paramPters are determined, the observer then sets the required rpm on 22, for rotation in the direction determined by 32; and the subject starts his ~more difficult~ runs with rod 12 rotating. When more "effort" on the part of the sub~ect is to be ascertained, in eithar the stationary run9 or the "rotating" run, 36 and 38 are normally rotated with respect to each other, the Allen bolt is re-set to apply more, or less, pressure on the ~hreaded rod 12, via the Fig. 5 combinations, to get additional "timel' figures for the same (stationary or rotary) run, but requiring more "effort" on the part of the subject.
Obviously once a given set of parameters are ascertained, these same parameters must be uniformly applied to all subjects in a glven group of ~, 3ubjects where comparisons with "norms", or wi~h other sub~ects within the same group are desired.

1. Evaluates one's overall degreP of persistence by tha actual ~ ;~
measurement of ~hree key factors in persistence:

a. Withstanding diacomfort to achieve a goal.
b~ Keeplng on at a task to achieve a goal. (Ploddl~g~
c. Constancy of effort in periormance of a task.

;~ 2. ~stimates a person's na~ural rhythm and pace of work based on his average rate o work performance on the PTA.

3. Assesses a person's overall de~ree of motlvation for work and industry by quantiyin~ one of the most accepted indicie~ o work motivatio~ -- one's degree of persistence.

4. With the evaluatio~ of a per~on's degree of persistence, coupled with hi~ average rafe of work perormance, a~ both are measured ;~ 30 on the PTA, an estimate can be made of a per~on's general level ~ of productivity.

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Claims (9)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. Apparatus for testing the persistence of an individual subject including a threaded rod, spaced supports for said rod, nut means movable along the portion of the length of said threaded rod between said spaced supports, power means connected to one end of said threaded rod, means for controlling the speed and direction of rotation of said threaded rod, and a tachometer connected to the end of said threaded rod opposite to said power means, and wherein the nut means includes a "split" nut having an internally threaded bore in each part thereof, each part being relatively rotatable with respect to the other part to regulate a braking or "drag" means located internally of one of the two parts.

2. The apparatus of claim 1 wherein a control panel including an on-off switch, a fuse, a clockwise rotation-off-counter clockwise rotation direction switch, and a calibrated scale for setting the rpm of an output shaft of said power source mounted thereon.

3. The apparatus of claim 2 wherein the tachometer has a range of approximately 30 rpm to 2000 rpm.

4. The apparatus of claim 1 wherein a deformable sleeve member bears against said threaded rod to provide (a) a braking means when the "split" nut portions are in one angular relation-ship, and (b) when the nut portions are in a second angular position with respect to each other, the braking effect is released and no "drag" is present on the threaded rod.

5. The apparatus of claim 4 wherein additional fastening means secure the "split" nut parts in each of their two positions.

6. The apparatus of claim 5 wherein there are three deformable sleeves, one in each of three smooth-reamed holes, spaced 120° apart radially of the axis of the nut means, held in place by three springs, and three short tips each having a conically-shaped nose portion, and each mates with a corres-ponding V-notch or conical depression in the internal periphery of the other "split" nut part.

7. The apparatus of claim 5 wherein the additional fastening means is an Allen bolt to lock the two "split" nut parts in each of their two positions.

8. Apparatus for testing the persistence of an individual subject including a threaded rod, nut means movable along a fixed portion of the length of said rod, said portion of rod being limited by standards supporting the rod, power means connected to one end of said threaded rod, means for controlling the speed and direction of rotation of said threaded rod, a tachometer connected to the end of said threaded rod opposite to said power means, and means connected to said nut means for varying the force necessary to move said nut means along said threaded rod.

9. The apparatus of claim 8, further including measurement means whereby the speed and direction of said threaded rod is measured.