Brown: Chapter 6 Flashcards
Several research designs are linked to inferential relationship statistics, such as:
Nonexperimental, cross-sectional relationship studies
Predictive studies
Case-control, cross-sectional predictive studies
Cohort studies in which data is prospectively or retrospectively collected over time
What is a Pearson product-moment correlation?
Describes the strength of the relationship between 2 continuous variables
Used in nonexperimental and cross-sectional relationship studies
What is a Spearman correlation?
Describes the strength of the relationship between 2 variables when at least one variable is rank-ordered
Used in nonexperimental and cross-sectional relationship studies
What is a linear regression?
Identifies predictors of a continuous outcome measure
Used in predictive studies
Several variables (predictors) are entered into a regression equation to determine how well they predict an outcome of interest (criterion); the outcome variable is continuous
What is an odds ratio?
Identifies predictors of a dichotomous outcome measure; best when the frequency of the outcome occurring is rare
Used in case-control and cross-sectional predictive studies
Best applied to cross-sectional studies in which the event or outcome has already occurred
What is a risk ratio?
Identifies predictors of a dichotomous outcome measure
Used in cohort studies in which data is either prospectively or retrospectively collected over time
Used to determine whether an event or outcome occurs
What is a hazards ratio?
Identifies predictors of a dichotomous outcome measure; often includes survival curve estimates
Used in cohort studies in which data is either prospectively or retrospectively collected over time
Provide information about the rate of change over time
What does this symbol mean: AR
absolute risk
What does this symbol mean: β
beta weight
What does this symbol mean: CI
confidence interval
What does this symbol mean: HR
hazards ratio
What does this symbol mean: N, n
number of participants in a study
What does this symbol mean: OR
odds ratio
What does this symbol mean: p
probability value; the likelihood of making a type I error
What does this symbol mean: r value
correlation coefficient
What does this symbol mean: R2
variance; the amount of variance accounted for in a correlational study
What does this symbol mean: R2 change
the amount of unique variance when a new variable or group of variables is added to a regression equation
What does this symbol mean: RR
risk ratio or relative risk
What is a correlation?
A correlation is a type of inferential statistic
that determines how much two or more
variables fluctuate together:
- Expressed in terms of strength, direction, and
significance
- Also represent effect sizes: the r value
What is explained variance?
the proportion of one data set that accounts for the spread of numbers in a second data set
What is a scatterplot?
a graph of plotted points that shows the relationship between two sets of data
What does this scatterplot show?
positive relationship
What does this scatterplot show?
no relationship
What does this scatterplot show?
negative relationship