Psych - Chapter 2 Flashcards
Significance testing and p value
p< .05, then we can conclude that an effect is present, and the difference between the two groups is real.
Provides info about the presence of an effect.
What is effect size?
A measure of magnitude.
If there is a difference between two experimental groups, how large is the difference?
Correlational coefficient - Pearson (r)
The most common statistical measure is the Pearson correlation coefficient, which is symbolized by the letter r.
Positive values of r (e.g., r = .54 or r = .67) indicate that the relationship is positive, whereas negative values of r (e.g., r = –.30 or r = –.72) indicate negative relationships.
The closer the coefficient is to -1 or +1, and the further away from zero, the greater the size of the association between the two variables.
Correlations of 0 indicate no relationship between the two variables.
Negative correlation
When someone scores high on one variable, and low on the other.
Eg. the age of a child, and the number of diaper they use in one day.
Positive correlation
When someone scores high on one variable, and high on the other.
Eg. Income level, and number of years of education
What is basic research?
Research that answers fundamental questions about behaviour
What is applied research?
Research that investigates issues that have implications for everyday life and provides solutions to everyday problems.
What is a theory?
Integrated set of principles that explains and predicts many, but not all observed relationships within a given domain of inquiry.
Stage of Theory of Cognitive Development
States that children must pass through a series of cognitive stages as they grow, each which must be mastered before entering next cognitive stage.
Correlation coefficient
Statistic that measures the association between variables.
Pearson correlation coefficient - symbolized by letter r.
Positive values r=.54, Negative r=-.54