Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
56 Cards in this Set
- Front
- Back
- 3rd side (hint)
hypothesis testing
|
whether a hypothesis is supported by the results of a research project
|
|
|
inferential statistics
|
drawing conclusions about a population based on data collected form a sample
|
compare measure of dependent variable in each group
|
|
null hypothesis
|
predicts that there is no difference between the groups being compared
|
there's no difference!
|
|
alternative hypothesis
|
a significant difference exists between the groups being compared
|
difference!!
|
|
one tailed hypothesis
|
researcher predicts the direction of the expected difference between groups
|
for a directional alternative hypothesis
|
|
two-tailed hypothesis
|
groups being compared differ but doesn't predict the direction of the difference
|
non-directional alternative hypothesis
|
|
type I error
|
difference, but in reality, there isnt
|
false alarms
|
|
type II error
|
there is a difference, when in reality there is
|
failed to reject null hypothesis
|
|
statistical significance
|
2 descriptive statistics that's unlikely to have occurred by chance
|
|
|
single-group design
|
one group of participants
|
|
|
z test
|
compare a sample with a population to assess whether the sample differs significantly from the population
|
tesing the null hypothesis on a single sample
|
|
sampling disitribution
|
a distribution of sample means based on random samples of a fixed size from a population
|
a distribution of statistics obtained by selecting all possible samples of a specific size from a population
|
|
standard error of the mean
|
standard deviation of the sampling distribution
|
|
|
critical value
|
value of a test statistic that marks the edge of the region of rejection in a sampling distribution, where values equal to it or beyond it fall in the region of rejection
|
|
|
region of rejection
|
area of sampling distribution that lies beyond the test statistic's critical value; when a score falls within this region, Ho is rejected
|
|
|
statistical power
|
probability of correctly rejecting a false Ho
|
test will correctly reject a false null hypothesis
|
|
confidence interval
|
interval of a certain width which we feel confident will contain population mean
|
|
|
t test
|
test of the null hypothesis for a single sample where population variance is not known
|
|
|
student's t distribution
|
curve was symmetrical, but it wasn't the standard normal curve
|
|
|
degrees of freedom
|
number of scores in a sample that are free to vary
|
|
|
z test
|
compare a sample with a population to assess whether the sample differs significantly from the population
|
how many SD above or below the mean score falls
|
|
sampling disitribution
|
a distribution of sample means based on random samples of a fixed size from a population
|
|
|
estimated standard error of the mean
|
standard deviation of the sampling distribution
|
|
|
chi-square
|
comparing categorical information against what we would expect based on previous knowledge
|
|
|
observed frequency
|
frequency with which participants fall into a category
|
|
|
expected frequency
|
requency expected in a category if the sample data represent the population
|
|
|
independent-groups t test
|
a parametric inferential test for comparing sample means of two independent groups of scores
|
between participants when participants are NOT matched
|
|
effect size
|
how big a role the conditions of the independent variable play in determining scores on the dependent variable
|
an estimate of the effect of the IV, regardless of sample size. is difference meaningful?
|
|
cohen's d
|
inferential statistic for measuring effect size
|
|
|
correlated-groups t test
|
compares the means of participants in 2 groups
|
comparing mean difference of correlated scores
|
|
difference scores
|
scores represnting the difference between participants' performance in a second condition
|
|
|
wilcoxon rank-sum test
|
nonparametric inferential test for comparing sample medians of 2 independent groups of scores
|
teacher ranks the female and male giving the student who read the fewest a rank of 1, and who read the most the highest rank.
|
|
chi-square test of independence
|
comparing how well an observed breakdown of people over various cateogries fits some expected breakdown
|
comparing how well an observed breakdown of people over various categories fits some expected breakdown
|
|
phi coefficient
|
an inferential test used to determine effect size for a chi-square test
|
|
|
bonferroni adjustment
|
desire alpha level is divided by the number of tests or comparisons, is typically used to accomplisht his
|
minimize chance of a type I error when making multiple comparisons, but increases type II error
|
|
ANOVA (analysis of variance)
|
comparing means of 3 or more groups
|
allows us to analyze the variance in a study
|
|
one-way randomized ANOVA
|
comparing means of 3 or more groups using a between-participants design and one IV
|
|
|
grand mean
|
the mean performance across all participants in a study
|
|
|
error variance
|
amount of variability among the scores caused by chance or uncontrolled variables
|
such as individual differences between participants
|
|
within-groups varaince
|
variance w/in each condition; an estimate of the population error variance
|
within-subjects: same people exposed to each level of IV
|
|
between-groups variance
|
estimate of the effect of the independent variable and error variance
|
between-subjects: different people are exposed to the each level of the IV
|
|
f-ratio
|
ratio of between-groups variance to within-groups variance
|
|
|
total sum of squares
|
sum of squared deviations of each score for the grandmean
|
how much each individual participant varies from the grand mean
|
|
within-groups sum of quares
|
sum of the squared deviations of each score from its group mean
|
|
|
between-groups sum of squares
|
sum of the squared deviations of each group's mean form the gran mean, multiplied by the number of participants in each group
|
|
|
post hoc test
|
comparing each of the groups in the study with each of the other groups to determine which ones differ significantly from each other
|
permits multiple compariosns and still manitain alpha (the probablity of a type I error) at .05
|
|
Tukey's honestly significant difference (HSD)
|
post hoc test used w/ ANOVAs for making all pairwise comparisons when conditions have equal n
|
allows a researcher to make all pairwise comparisons among the sample means in a study while mantaining an acceptable alpha (usually .05 but could be .01)
|
|
one-way repeated measure ANOVA
|
comparing the means of 2 or more groups using a correlated-groups design and one IV
|
mesares are taken repeatedly on the same individuals; same participants serve in all conditions
|
|
factorial design
|
more than one IV
|
|
|
factorial notation
|
how may IVs are used in a study and how many levels are use for each variable
|
each number in the notation specifies the number of levels of a single IV. 3 x 6 has 2 IVs, one IV has 3 levels the other 6.
|
|
main effect
|
an effect of a single independent variable
|
2 IVs may have 2 main effects, an effect of word type and an effect of rehearsal type
|
|
interaction effect
|
effect of each IV across the levels of the other IV
|
interaction between 2 IVs, effect of 1 IV depends on the level of the otehr IV
|
|
treatment carryover effect
|
earlier treatment affects later treatment
|
|
|
sensitization effect
|
performance changes due to hypothesis guessing
|
|
|
practice effect
|
performance improves later mesaures
|
|
|
fatigue effect
|
performance declines on later measures
|
|