1why can't we use z score in skewd tests ?
z score : 1,1 migh actually be pretty normal
z score assumes normal distribution
2what test do we use in skewed ?
normalized standard scores
only with large group
3how do we get to the normalized score?
base on precentile
1. raw → precentile
2. precentile → equivalent z score = normalized standard score
3. use z score as normalized standard score
4how are normalised standard scores ?
non linear as they are basing them on percentiles
5what does the non liniar transformation tell us ?
raw score charcteristics distorted
different correlations
6what are other normalized standard score ?
stanine
c score
sten
7what are the M and SD of stanine ?
M = 5, SD = 2
8what are the M and SD of c score ?
M= 5, SD = 2
9what are the M and SD of sten ?
M =5.5, SD= 2
10how do we compare norms for different tests?
tranform both in the same score
11how do we tranform a z score into a t score ?
12how do we transform a t score into a z score ?
( T score _ 50 ) / 10 = z score
13which way of comparing tests is better ?
transform z score to t score is better
14what is the goal of absolute norms ?
1. criterion referenced
2. domain referenced
3. developmentally
15what types of absolute norms are there ?
1. summative assesments
2. formative assesments
16what are summative assesments ?
slection / qualification / prognosis
MTA1 exam
17what are formative assesments ?
tells us something about strengths and weaknesses
aim is to instruct
pollas / feedback
18what are the norm requirments ?
1. representativeness
2. size
3. placement
19what does representativeness mean ?
take into acount many characteristics : → who is the test for
sex
age
class
education
ethnicity
religion
city \ rural
20what methods of sampling are there?
1. randomn sampling
2. stratisfied randomn sampling : look at charcteristics and try to include all of them in the same ratios
21what size requirments are there for important decisions ?
important decisions :
good more than 400
sufficinet between 300 and 400
insufficient less than 300
22what duraility requirments are there ?
1. timely
after 15 years outdated
after 20 years no longer usable
2. societal changes
3. educational changes
23what subgroups requirments are there?
relavant norm groups in regards to age,sex, ethinicity and region ( rural / urban )
class and grade must be taken into consideration
24what is the Flynn effect ?
ncrease in both fluid and crystallized intelligence test scores that were measured in many parts of the world over the 20th century
25what information do we need to determine when a score no longer "normal"?
severity
characteristics and traits of the person
we can use arbitrary or test specific
26what are the most common intervals of normality ?
high more than 2 SD
above average more than 1SD
average between _1 and 1 SD
below average more than 1SD
low more than 2 SD
27what specifications do we need to create a norm table ?
range score
mean
standard deviation
28how do we determine the cut off average ?
→ high scores : mean +2SD up until maximum
→ above average : more than mean + 1SD
→ average scores : between mean + 1SD and mean _ 1SD
→below average : mean _ 1SD
→ low scores : between minimum and mean _2 SD