what is the term that is used to describe the relationship between two variables?
correlation
what is used to quantify the relationship between two continuous variables ?
Pearson’s r
what are trying to identify in asking relationship questions?
trend
what kind of question is this: as scores on X go up , what happens to scores on Y?
relationship questions
when do we use scatterplots? how?
data for a correlation, for each observation a dot is placed at the point at which the X and Y scores intersect
what helps us describe both the direction and the strength of the correlation?
scatterplots
what kind of correlation has scores on the two variables tend to move in the same direction?
postive correlation
what kind of correlation has the two variables inversely related?
negative correlation
does the correlation get stronger as the plot approaches a straight line, and reaches a maximum when all data points fall directly on a line ?
yes
what gives the direction of the correlation in pearsons r ?
the sign of r + or -
what gives the strength of the relationship of pearsons r?
magnitude
what simply describes the degree of relationship between two variables
correlation
what are observations that do not fit the overall trend of the relationship and can increase or decrease the value of r?
outliers
what are relationships described by a curved line and will decrease the value of r?
non-linear trends
scores are not obtained along the entire range of the scale for x and/or y and will decrease the value of r?
restriction of range
what is the coefficient of determination?
r2
what is the proportion of variability in one variable explained by variability in the other variable?
coefficient of determination
one continuous and one categorical variable with only two groups:
point-biserial correlation
at least one variable is ordinal
spearman’s rho
two dichotomous categorical variables
phi
two categorical variables with any number of categories
cramers c or v
-
Module 4-Beyond the Evidence Hierarchy: Reliability & Validity issues40
-
Module 4- part 256
-
mod 5.1- understanding descriptive statistics19
-
mod 5.2- critical appraisal of diagnostic studies20
-
Mod 5.3 prognostic studies18
-
6.1: Inferential statistics19
-
6.2 t-Tests parametric testing5
-
6.2 b ANOVA12
-
6.2 c Correlation21
-
6.3 Non parametric testing17
-
Module 7.1: appraisal of RCTS16
-
7.2 introduction to SRs16
-
7.3 understanding clinical practice guidelines6
