MIRC October 9, 2007 –
Soc 497 Fall 07
<jerry> First, do we all
remember the format of the test..
<jerry> There are three
parts..
<jerry> 1) objective (MC and TF)
<Judy> yes
<jerry> 2) definitions
<jerry> 3) short answers
<jerry> There are 50 points.
<jerry> No scantrons or bluebooks needed..
<jerry> Do we have that down?
<jerry> Judy, do we
understand that much?
<Judy> yes
<jerry> okay, second issue
then..
<jerry> this test deals only
with the material covered since the last test..
<jerry> that means three
things:
<jerry> 1) measurement control
<jerry> 2) experimental control
<jerry> 3) statistical control
<jerry> taken together, #1 is
the first part of an operational definition..
<jerry> that is, a
measurement unit..
<jerry> while the last two
have to do with the "procedure" in an operational definition
<jerry> Does that resonate,
Judy?
<Judy> yes
<jerry> okay, then it remains
to structure your knowledge of these three components to have a successful
test.
<jerry> first, measurement
control..
<jerry> there are three
issues I would like you to remember..
<jerry> the first is the
levels of measurement..
<jerry> can you name all
four?
<jerry> Judy?
<Judy> Nominal, ordinal, interval and ratio..right
<jerry> good
<jerry> please know what they mean and what operations are implied by each..
<jerry> The second issue is
the process of imposing operational definitions..
<jerry> that is, nominal
concept, indicator, operational definition and variable..
<jerry> to answer your
question, an indicator is simply an intervening conept
more precise than...
<jerry> a nominal concept,
but less operational than an operational definition..
<jerry> The third issue has
to do with the reliability and validity of a concept..
<jerry> remember reliability
means consistency and validity means accuracy..
<jerry> what are the two
types of reliability?
<jerry> Judy?
<Judy> test/retest and split half
<jerry> good.
<jerry> and what are the four
types of validity
<jerry> Judy?
<Judy> sorface, construct, criteron, predictive
<Judy> i ment
face on the first one
<jerry> good
<jerry> study these three
issues having to do with measurement...
<jerry> and you should be
okay.
<jerry> The second major
topic of this test..
<jerry> is experimental
control..
<jerry> please know four
things..
<jerry> 1) the definition of experimental design..
<jerry> 2) simple designs.
<jerry> 3) complex designs
<jerry> 4) quasi designs.
<jerry> what three things do
you need for an experiment?
<jerry> Judy?
<jerry> they are:
<jerry> 1) at least two groups
<jerry> 2) random assignment
<jerry> 3) measurement of an outcome
<jerry> do you remember these?
<Judy> forgot the lat one
<jerry> okay, please reflect
on what they mena.
<Judy> ok
<jerry> make that "..they mean".
<jerry> secondly, remember
that simply designs mean one IV...
<jerry> and complex designs
mean two or more IVs.
<jerry> that complex designs
are done precisely so that we can interpret "interaction" effects.
<jerry> remember, for
example, what a 3 x 2 CRD means:
<jerry> 1) two IVs
<jerry> 2) three attribute on one variable and 2 on
the other;
<jerry> 3) a total of six conditions
<Judy> got it
<jerry> also, remember that
when designs get too big, ...
<jerry> we try to conserve on
subjects...
<jerry> either by taking some
of the conditions out of the design...
<jerry> or reusing subjects..
<Judy> ok
<jerry> finally, remember
that a quasi-design is missing one or more conditions of a true experiment
<jerry> typically lack of
random assignment..
<jerry> finally, the Third
critical topic is statistical control..
<Judy> ok
<jerry> meaning that we need
to sample our populations to include those with the attributes of...
<jerry> variables we deem to
be potential noise or exogenous variables.
<jerry> the difference
between the attempt to engage internal validation through experimental
control...
<jerry> and external
validation through sampling...
<jerry> is precisely the
difference between taking charge of the variables and holding them constant..
<jerry> vs. measuring them in
their naturally occurring setting and statistically holding them constant..
<jerry> I suggested to you
that there are two types of samples..
<Judy> probability
<Judy> and non probability
<jerry> and?
<jerry> good, what is the
difference between the two re: a sampling frame?
<Judy> probability uses simple random sample
<jerry> well, it uses more
than that..
<jerry> but which has a
sampling frame, probability or non-probability samples.
<Judy> well it uses random smples
while non-probability uses samples such as convenience
<jerry> but what of my last
question, which uses a sampling frame?
<Judy> non
<jerry> nope..
<jerry> remember a sampling
frame is a listing of the population elements..
<Judy> by sampling frame do you meen
a system to get randm samples
<jerry> nope, see above; a
listing of the population elements
<Judy> ok
<jerry> without such a list,
we cannot calculate the "probability" of an element occurring.
<jerry> hence the term,
non-probability
<jerry> please study the
difference..
<jerry> also, please be able
to articulate different types of probability samples.
<jerry> and non-probabiliy samples..
<Judy> theres 4 types that i need to know
<jerry> yes..
<Judy> and 3 for non..correct
<jerry> yes
<jerry> finally, you need to
know about the size of a sample
<Judy> the formula
<jerry> please understand
that there are three issues having to do with size
<jerry> can you name them?
<Judy> Error in prediction
<jerry> yes
<Judy> confidence interval
<jerry> yes
<Judy> variability in population
<jerry> good
<jerry> these are the
essential concepts for our test..
<jerry> now, do you have any
questions?
<Judy> not @ the time
<jerry> okay, then I will see
you on Thursday
<Judy> thank you so much
<jerry> you are welcome