Experimental research methods.

Key words. experimental, non-experimental scientific, non-scientific sample population IV, DV, EV Statistical significance Operational.

Group of participants selected from and representative of a population of research interest. Must be representative of population from which it is drawn for results to be accurate. Is a logically stepped process used for investigating and acquiring or expanding our understanding. The findings can be reproduced and demonstrated to be consistent. A number obtained from interdental statistics that provides an estimate of how often experimental results could have occurred by chance alone, or by the independent variable. Involves at least one independent and at least one dependent variable. An experimenter is able to manipulate these variables to identify a cause-and- effect relationship. any variable (other than the IV) that may cause a change in the results of, and therefore may have an unwanted effect on the experiment

Operational hypothesis. A testable prediction about the direction of interaction between variables (i.e. higher, lower, increased, decreased). The population from which the sample is drawn The independent variable operationalised The dependant variable operationalised