PSY 53 Exam 1
normal distribution
bell-shaped curve
You want a graphical presentation of the median, lower 25th percentile, and upper 25th percentile. What do you use?
box and whiskers
discrete variable
can take only certain values (usually whole numbers) on the scale.
When items on a questionnaire appear to correspond to the construct that the questionnaire claims to measure it is said to have:
criterion validity
inferential statistics
data from a sample, using that data to make an inference of the broader population
descriptive statistics
describing the data that is in front of you
between-groups design
design making comparison between two different groups of people
cohen's d
effect size
social comparison
figuring out how you compare to someone . (upward:comparing yourself to someone who is above you) (downward comparing yourself to someone below you)
The degree to which a statistical model represents the data collected is known as what?
fit
platykurtosis
flat not much difference between mode and height [Flat]
You want to see if a variable has a normal distribution. What kind of graph do you use?
histogram
practical significance
how big of a difference there was
variance
how far numbers are spread out squared standard deviation
z-score
how many standard deviations you are away from the mean
mortality salience
how much death is on your mind
predictor
if i only knew one variable I can use it to predict another variable
An experimenter measured 30 children's IQ. He then rank-ordered the children and assigned them a score from 30 (most intelligent) to 1 (least intelligent) to create a new variable. Does this new variable consist of:
interval
continuous variable
is on that gives us a score for each person and can take on any value on the measurement scale that we are using
criterion validity
is whether you can establish that an instrument measures what it claims to measure through comparison to objective criteria.
negative skew
left side tail
within subjects design
making a comparison in the same group
concurrent
measure both at the same time
If we calculated an effect size and found it was r = .42, which expression would best describe the size of the effect?
medium to large
Leptokurotosis
more scores are at the mode less people at the extremes
degrees of freedom
n-1
For which type of measure is it important to create value labels?
nominal
mesokurotic
normal distribution good proportion of people at the mode and tails.
type 1 error
occurs when we believe that there is a geniunine effect in our population, when in fact ther eis not
type II error
occurs when we believe that there is no effect in the population when in reality, there is
practice effects
participants may perform differently in the second condition because of familiarity with the experimental situation and/or the measures being used
boredom effect
participants may perform differently in the second condition because they are tired of bored from having completed the first condition
kurtosis
ratio of the height and mode of the tails. you have kurotosis from = away from zero
Variation due to some genuine effect is known as
residual variance
positive skew
right side tail
What is the relationship between the sum of squared errors (SS), the sample size (n) and the variance (s2)?
s2=SS/(n-1)
You want to see if two variables are related to each other. What kind of graph do you use?
scatterplot
promotion
seeking the good stuff
two-tailed test
test a non-directional hypothesis
power
the ability of a test to detect an effect of a particular size
counterbalancing
the area of variation between upper and lower limits on a scale
homogenous variance
the assumption that the variance of one variable is stable at all levels f another variable
systematic variation
the variation is due to the experimenter doing something in one condition but not in the other condition.
histogram
used for interval and ratio data
residual variance
variation due to some genuine effect
statistical significance
whatever effect you get how likely you got it by chance if the null were true
ordinal
when categories are ordered
nominal
when two things that are equivalent in some sense are given the same name but there are more that two possibilities.
falsification
which is the act of disapproving a hypothesis or theory
content validity
with self reports measures/questionnaires can also assess the degree to which individual items represent the construct being measured, and cover the full range of the construct.
ratio
you can double it.
You are a not quite honest advertiser, and you want to show a graph that makes it seem that people who use your product live a lot longer than people who use a competitor's product. What can you do?
Put as small as possible of a range of scores on the Y axis
Why does the syntax window exist?
So you can save analyses that you've done to re-do later
If we use the mean as a model, what does the variance represent?
The average error between the model and the observed data
What are labels used for?
To help you see what a variable was
In which window of SPSS do you name and define variables?
Variable view in the data window
standard deviation
a far apart of the mean people are. Average distance away from the means
You're in the data view of the data window. What does a row represent?
a person
one tailed test
a statistical model that tests a directional hypothesis
unsystematic variance
anything that will introduce noise to a study
ecological validity
applying it to real life settings
prevention
avoid bad stuff
Given a test is normally distributed with a mean of 30 and a standard deviation of 6: What is the probability that a single score drawn at random will be greater than 34?
0.254
meta analyses
1) across these sizes what the average effect size. 2) what explains if effect size are small or big
The owner of the large chain of coffee shops called 'MoonBucks' decided to calculate how much revenue was gained from lattes each month in a nationwide sample of 2445 cafés. To measure the variance of revenue gained from lattes, he computes SS = 351,936 for this sample. What are the degrees of freedom for variance?
2444
how many variables are in the findings depicted in this chart
3
wenty-one cats were given 300g of tuna each. The time in seconds was measured until they had eaten all of the tuna: 16, 18, 18, 22, 22, 23, 23, 24, 26, 29, 32, 34, 34, 36, 36, 42, 43, 46, 46, 49, 57 What is the median time to eat the tuna?
32 seconds