## intro to stats and research design

What is a variable any observation of a physical, attitudinal or behavioral characteristic that can take on values
What is a discrete observation can take on only specific values–whole #– no other values can exist between these numbers
What is a continuous observation can take on a full range of values–number out several decimal places– an infinite number of potential values exists
What is nominal variables a variable used for observations that have categories or names as their values
What is an ordinal variable a variable used for observations that have rankings such as 1st, 2nd, 3rd…
What is an interval variable a variable used for observations that have numbers as their values and the distance or interval between pairs of consecutive numbers is assumed to be equal
What is a ratio variable a variable that meets criteria for an interval variable but also has a meaningful zero point
What is a scale variable A variable that meets the criteria for an interval or a ratio variable
What is a level a discrete value or condition that a variable can take on
What is an independent variable a variable that we either manipulate or observe to determine its effects on the dependent variable
What is a good variable reliable and complete
what is a dependent variable the outcome variable that we hypothesize to be related to or caused by changes in the independent variable
What is a confounding variable any variable systematically varies with the independent variable so that we cannot logically determine which variable is at work also called a confound
What is reliability Refers to the consistency of a measure
What is validity the extent to which a test actually measures what was intended to measure
What is hypothesis testing the process of drawing conclusions about whether a particular relation between variables is supported by the evidence
What is operational definition specifies the operations or procedures used to measure or manipulate a variable
What is correlation an association between two or more variables
What is an experiment a study in participants are randomly assigned to a condition or level of one or more independent variables which par
What is a random assignment every participant has an equal chance of being assigned to any group or experimental condition in the study
What is an between–groups research design participants experience one, and only one ,level of the independent variable
What is a within–groups research design the different levels of the independent variable are experienced by all participants in the study also called a repeated- measure research design