research methods: experimental method and control of variables Flashcards
what is a hypothesis?
A precise testable statement about the expected outcome of an investigation. Stated at the onset of a study
what is an aim?
A general statement of what the researcher intends to investigate; the purpose of the study
what is an experiment?
A controlled situation in which the researcher manipulates one variable to discover its effect on another variable while the other variables are held constant. It allows us to establish cause-and-effect relationships
what is an alternative/experimental hypothesis?
A hypothesis which predicts that there will be a significant difference in the results between the two conditions
what is a null hypothesis?
A null hypothesis predicts no difference between two variables.
what is a directional/one tailed hypothesis?
Specifically predicts two directional predicted results. includes words like more or less, decrease or increase etc
what is a non-directional/ two tailed hypothesis?
Does not state the direction of the results but states that a difference will be found between the conditions. typically says there will be an effect/no effect
when will psychologists tend to use a directional hypothesis?
When the findings of previous research suggest a particular outcome
when will psychologists tend to use a non-directional hypothesis?
When there is no previous research or findings from earlier research are contradictory
what is an independent variable?
The variable that the researcher manipulates
what is a dependent variable?
The variable that is affected by the changes in the independent variable. the variable that is measured by the researcher
