Although it is not common for a researcher to state explicitly that
a convenience sample was used, it will be obvious from the subjects sub section of article. If some type of probability sampling procedure was used it will be described. Thus, in the absence of such particulars
you can assume that amples are typical.
sample was an available one. The following
ing 114 subjects.”(Carrier and Williams, 1988, pp. 291-292)
7 were not included in the
for various reasons,
in the study were sixth
at a public school in a suburb north of Minneapolis, Minnesota. Of the total
65 students were
and 56 were
: ‘., ,(
grade stud& e&&U
eirls. tinal analy&
,~j~,“Participants ::: ?‘:.:number. !:.:,,subjects, ;. :
.: _ ‘ ” . > : _ ; . . : _ : , : . , _ : , _ _ _ _ s : . d o n v e n l ~ n ~ ~ . S a r n p i ~ ) .: I ..,. ‘ * ::. ) . I :..
:, $ ..
“Twelve volunteer third-grade teachers and their students participated in the study. The teachers were employed in 10 public schools located in three school districts in suburban areas of northern California.” (Mitman.
“The initial group of subjects in- this study was composed of 42 under- graduate secondary education students majoring in a variety of They were about to be placed in classrooms to student teach for first semester. Thirty-five of these students also participated in the part of the experiment at the end of the semester, following a
student teaching experience.”
and Buck, 1987,
i I. :: ! ,: “;
:j 1’. $1: plines,
‘ their ~. .. 8 ,
?~.‘.concluding !:: lOweek
“The study was conducted in a school system of approximately 2,800 school students attending 6 schools. All kindergarten and
first grade teachers using
ability grouping were asked to
Of 22 teachers invited to
20 agreed and were
8 ) subsequently observed.” (Haskins, Walden and 6 7 - 8 6 8
:‘.‘: :.;:elementary :. :~;,patticipate. :__
2 .a ; t :
Sampling In purposive sampling (sometimes referred to as
topic. Based on the researcher’s knowledge of the
sampling) the researcher selects par-
will be representative or in-
pwposeful, judgmat or judgmental tic&r the the
population, ajudgment is made about which cases should be selected to provide the best information to address the purpose of the research. For example, in research on effective teaching it may be most informative to observe “expert” or “master” teachers rather than all teachers. To study effective schools it may be most informative to interview key personnel, such as the principal and teachers who have been in the school a num- ber of years. The use of “selected precincts” for political polls is a type of
~uqxxive P articularly ‘Wects.
sampling: Selection of