evaluating psych
Terms
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 type II error

may fail to reject Ho when it is false
BETA LEVEL:prob type II error (.20 or 20%)more willing to accept  power

degree to which research design sensitive to effects of IVdetect effects IV more easily than less powerful designs
 #participants in study
< # < detect effects IV on DV(magnitude)  power analysis

determine # participants needed order detect effect IV
aim exceed .80  effect size

proportion variability in DV that is due to IV
.00 to 1.00  Ttest
 analyze data from 2 group randomized exper./its error/variance we see random?
 1. directional hypoth and 2. non directional hypoth

1.states which of 2 conditions means is expected to be larger
2.states 2 means are expected to differ, no prediction which is larger  1.one tailed test vs. 2.two tailed test

1.used to test directional hypoth.
2.hypoth is nondirectional  paired ttest

used when exper. involves matched subj. or w/ in subj. design
participants 2 conditions similar if not identical related to DV 
paired ttest
1.matched subj design
2.w/ in subj design 
1.randomly assign matched pairs to two conditions
score up DV in one then score up DV other situation
2.same participants serve in both conditions
 (+) corr. obtained btw. matched scores  stat. significance affected by 3 factors

1.SAMPLE SIZE:larger size more stat sig.
2.MAGNITUDE CORR:larger value r less likely be .00
3.NOT DRAW IN CORRECT CONCLUSIONS:sig. diff from 0 if there is >5% chance corr. as large as one obtained could have come from pop. w/ true corr. zero
>.16 corr. could be 0
.10 weak magnitude/.30 moderate/.50 strong  deonotology
 ethical approach maintaining right and wrong be judged according to universal moral code
 ethical skepticism

denies exist concrete and inviolate moral codes
relative culture and time  utilitarian

judgement action depend on consequences of that action
APA uses this  costbenefit analysis
 weigh pros and cons fo study
 benefits behavioral research
 when cost benefit analysis is conducted
 basic knowledge
 up risk and cost ok when research up
 improve research/assessment techniques
 moe research like this improve research itself/ more reliable, valid,useful/efficient methods
 practical outcomes

up welfare subjects
better drugs/treatments  benefits researchers
 education function first hand research
 cost

balance risk and cost
$ involved conduct actual research
deception=distrust toward research  balance benefits and cost

down benefit down cost and vice versa
research approved by IRB  informed concent

inform nature study and agree to participate
inform about features research influencce willingness to participate
pain discomfort
IC form usually used
IC given orally some cases only if witness present  ?IC

COMPROMISING VALIDITY STUDYact diff if watched
UNABLE GIVE ICchild, mental handicapped/ parent/legal guradian give IC
GREATER BURDEN OBTAIN IT THAN NOT
intersection street!
min. risk, not affect rights &welfare, not carried out if required  invasion privacy

no strict guidelines
study w/ out person knowledge judgements left to investigator  coercion participate

prof. require students participate research studies
paper option=research time lab  physical and mental stress

difficult study when expose small amounts phy. mental stress
lead beleive dying=NO!!
decisions made costbenefit analysis research  deception research

use confederate
false feedback
related studies as unrelated
incorrect info reguarding stimuli materials  objections deception

lying and deciet immoral?
ends justify means
violation moral rules
widely used enter knowing this suspicious researcher tell them right away
distrust behavioral scientist & research in gen.
participants do not view decep. as same as lying! informed after ok!!  debriefing

when deception used must use this!
1. clairfy study explain reasons deception occured
2. remove excess stress or ()consequences
3. obtain participants reactions/feedback on study
4. leave feeling good about study  confidentiality

only purpose for research
ensure responses anonymous
give codes label data
ex:milgram exper= obedience  reserach with animals
 same as humans only different guidelines to follow
 scientific misconduct

ethical standards memb. guard against this
1. fabrication, falisfication, and plagiarism
2. fail report data not with their own views or making data availiable who wish to varify their data
3.research participants that are problematic (what order authors go)
4. sexual harrasment/abuse power, discriminate, or failure follow gov. regulations
5. conduct poorly designed research  factors distort corr. coefficients

1.RESTRICTION RANGE:narrow rep. data
misleading or weak corr?
2.OUTLIERS:deviant from remainder of data
further 3 SD away from mean
3.RELIABILITY MEASURES:>reliable measure, down corr. coeff. will obtain  corr. and causality

CORR. DOES NOT IMPLY CAUSALITY!!
even if perfectly corr.
basis tobacco company claim against cigs and lung cancer  partial corr.

can conclude particular causal explaination of relatiohship btwn variables more likely be correct than are other causal explainations
x and y corr
=x may cause y/vice versa/some ther var. cause x and y
corr. btwn variables stat. removed
eliminate 3rd variable possible influnece
see if x and y stil corr.  analyzing experimental data

diff. group ave. suggest IV had an effect
can not draw conclusions about effects IV simply by looking only at means of experimental conditions  crosssectional survey

single group
char. that group/various groups differ  sucessive indep. samples survey

2 or more samples of respondents answer same ? at different pts. in time
validity on if each selected same way  longitudinal

single group/ long time
changes in behavior studied  demographics

describe patterns basic life events and experiences
birth, marriage, employ, migration, death  epidemiological research

study occurances disease diff. groups people
info groups at risk illness/injury  surveys
 all pic. how large groups tend think, feel and behave
 sampling
 way select people for study from population of interest
 representative sample
 one which can draq accurate, unbiased est. char. larger pop.
 sampling error
 cause reseults obtained sample diff. entire population
 error estm.

(margin error) degree data obtained sample expected deviate from pop. as whole
condfidence expressed in term error estm.
down error estm. more close resuls from sample estm behavior large pop.
function sample size, pop size, variance data  economic sample

reasonably accurate estm. of pop. reasonable ost and effort
error estm down when pop. up
larger variance up sample must be  probability sample
 prop and indiv in pop. will be included
 epsem design

specifies all cases in pop have= prob. being chosen for sample
"equal prob. selection method"  simple random sampling
 every possible sample desired size same chance being selected from pop.
 sampling frame
 list pop. sample comes from
 table random #'s
 use with large pop
 stratified random sampling
 variation SRS divide pop. into 2 or more strata
 stratum

subset pop. shares particular char.
compare 2 group with in this  cluster samp
 sample group participant based naturally occuring groups/get list/randomly select list from that group
 multi stage process

no sample frame needed
less time/ effort needed contact participants  error variance cause mean diff

means may differ even if IV does not have an effect
CONFOUNDING VAR:portion total variance in set scores due to extraneous variable that differ systematically between experimental groups (2ndary variance)
error variance in data ave recall 2 groups of participants likely differ slightly even if treated the same
indiv. differences  nonresponse problem

failure obtain responses indiv researches select from sample
data may be bias was impossible determine
representativeness of sample compromised
same with tele surveys
1.take steps to increase response rate
2.if respondents and nonrespondents differ in any systematic ways  non prob samples

no way knowing prob. a particular case will be choosen for sample
not calculate error estm.
limit ability generalize
test how variable relate to research test hypoth.
external validity assessed through replication
sim. findings validity up  convenience sampling

readily avaliable used
prob. using college students
more intell. than gen. pop.  quota sampling
 certian kind participants obtained particular proportions
 purpose sampling

use judgements decide which participants include in sample
try get respondents typical of pop.
elections use this 
describing and presenting data
critera good one 
accuracy, conciseness, and understandability
RAW DATAall participants scores on all measures
selecitve data present=clearly describe results
description understood  numerical methods
 sum data from # as % or means
 graphical methods
 present data graphically or pictorial form (graphs)
 frequency distributions
 table sum raw data # scores fall with in each several categories
 simple frequency distrib.

# participants who obtained each score
up or down
2nd column frequency 
inferential stats
(solution to error variance cause mean diff) 
conclude independ. var. has effect when diff. btw means experimental conditions larger we expect to be when diff due solely to effects of error variance
compare diff btwn means of exper. condition of diff. expect to obtain based on error var.
never know for sure
can specify probability  group frequency distrib.

frequency subset of scores
break range scores several subsets(class interval)=size  hypothesis testing

Ho:IV no effect on DV
H1:IV did have effect of DV
REJECT Ho:IV did have effect on DV
FAIL TO REJECT:IV did not have effect of DV  relative freq.

proportion total # scores tells each class interval freq. class interval % total # scores
class interval are ME
capture all possible reponses
all class interval same size
freq. info=histogram/bargraphs/ freq. polygon  type I error

researcher concludes IV had effec on DV when the observed diff. btwn means of experimental conditions actually due to error variance
ALPHA LEVEL:prob. making type 1 error
.05 or 5% (>.05 reject)
STAT SIGNIF:when reject Ho with low prob. making type 1 error refer diff. btw means  measures central tendency

convey info. about distrib. providing info about ave/ most typical
MEAN:ave (can be misleading)
MEDIAN:middle
MODE:most often  measure variablility

know how much scores distrib. vary
descriptive stat convey info. spread/ var. set data
RANGE:least useful set on two extremes
VARIANCE:takes into account all of scores when calc. variability of set of data
SD= it's square root
index ave. amount variability in set data
purpose stat. analysis  zscore

particular participants score relative to rest of data (standard score)
z=(y1y)/s 
SD and normal curve
normal distribution 
having mean and SD estm. percent participants who obtained certian scores
tell distrib. across various ranges of scores
useful identify extremes/outliers
very high or very low zscore
(3.00 or +3.00)  sucessive independent

crosssection with time component
different people/repeatedly  SD

I 34.13%68%
II 13.6%94%
III 2.14%98%
IV .13%99%  corr. research

whether var. are related to one another
relatiohship btw. 2 or more naturally occuring variables  Pearson CC

(r)
interp. consider 1.sign and 2.magnitude
1.direction (+) positive relationship(up and up)
optimism and health corr.
()=inverse or negative relationship btw 2 var (up and down)
2.numerical value ignore sign
strength relation between variables
.00 not linerly related  corr. coeficients

1 to +1
strength and direction relationship
only requirement obtain scores on 2 var. for each participant in our sample  1.scatter plot, 2.perfect corr, 3.zero corr.

1.graph representation participants scores 2 variables
2.(1.00 to +1.00)
3.no pattern  coefficient of determination
 x2 of corr. coefficient; indicated proportion of variance 1 var. can be accounted for by other var.

1.variance
2.systematic variance
3.error variance 
1.amount var. in set data
2.part total var. in participants responses related var. researcher is investigating
3.portion total variance unrelated to variables under investigation  stat. significance of r

corr. coeff. calculated on a sample has very low prob. being zero in pop.
b/c sampling error never get r=.00 even though true corr. pop is zero
>.05 stat signif. 
Joe Brady:
executive monkeys experiment 
Type II error
monkeys first group moved on to the second group only if did good in phaseI
actually looked at two diff populations of monkeyes
confounding variables
found monkey A (the boss) had more ulcers  Weis

same study as brady but found opposite
monkey b more than monkey A got ulcers 
Jarrard:
LSD experiment 
rats press for food (motivation)
problem results:
could be a build up of LSD in system cause drastic decline btwn .2 and .4
better:take 6 diff rats and give them each dose (use latin square)  counter balancing

procedure used within subj. designs in which diff participants recieve the levels of IV in different orders
used to avoid systematic order effects 
btw group:
1.pros and 2.cons 
1. faster, someone drops out find another just like them, everyone diff indiv impact
2. more $, less power, very difficult match subjects 
w/ in groups:
pros and cons 
1. more power, every person own control group, removes error from indiv variability
2. longer, slower, when someone drops out problematic  1.carryover effect and 2.order effect

1.a situation in w/in subj. designs in which the effects of one level of the IV are still present when another level of IV is introduced
2.an effect on behavior produced by specific order in which levels of the IV are administered in a w/in subj design 
Greene 1996 Memory Test
study list>delay (5sec and 20sec)
*do both with in and between subj. designs* 
results: with in better becasue found diff where as with between found no difference
WITH IN BETTER!!!!! 
counterbalancing:
complete and incomplete 
complete= what lit for levels?
3 conditions
incomplete= latin squares
doesnt count for all possibilities