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EMPLOYMENT  PSYCHOLOGY

6.  Q.  Why  chamber?  A.  If  the  chamber  is  too  large
the  shell  will  swell  and  cannot  be  extracted  in  the  regular
way.
7.  Q.  Why  firing  pin?  A.  If  the  firing  pin  is  too  long
there  will  be  the  danger  of  premature  fire,  if  too  short,  of
misfire.
8.  Q.  Why  barrel?  A.  If  there  is  a  seam  in  the  barrel
when  shot  it  will  burst  open  and  if  the  barrel  is  not  straight
the  gun  will  not  shoot  straight.
9.  Q.  Why  sight  alignment?  A.  The  alignment  of
sight  is  essential  to  correct  shooting.
10.  Q.  What  experience  as  an  assembler  other  than  on
guns?  A.  Have  had  several  years’  experience  on  sewing
machines,  typewriters,  etc.
11.  Q.  What  kind  of  work  requiring  particularly  close
filing  have  you  done?  A.  Small-tool  work.
These  are  valuable  questions  because  they  require
specific  answers  about  concrete  and  specific  elements  in  the
work  of  gun  assembling.  However,  definite  as  they  are,
they  could  not  be  used  as  they  stand  with  any  certainty  as
to  their  value.  It  is  first  of  all  necessary  to  experiment
with  these  questions  on  a  sufficient  number  of  men  actually
engaged  in  this  work,  in  order  to  find  out  whether  the
questions  are  such  that  the  best  workers  obtain  the  highest
grade  in  the  test  and  the  poorest  workers  the  lowest
grade.  In  other  words,  it  is  necessary  to  find  the  correlation ­
  between  the  performance  of  the  men  in  the  test  and
their  actual  ability  at  their  trade.  Moreover,  it  is  also
necessary,  by  the  process  of  trial  and  error  described  in
previous  chapters,  to  eliminate  ambiguous  words,  catch
questions,  “guess”  answers,  and  questions  which  permit
a  lengthy  or  indefinite  explanation.  In  short,  trade  tests,
whether  in  the  form  of  questions  or  any  other  form,  must