SOME NEWish KEY TERMS.docx

**SOME NEWish KEY TERMS:** **standard deviation** statistic that summarises how far scores within a set of scores spread out, or deviate, from the mean for those scores --------------------------------- ---------------------------------------------------------------------------------...

**SOME NEWish KEY TERMS:** **standard deviation** statistic that summarises how far scores within a set of scores spread out, or deviate, from the mean for those scores --------------------------------- ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- **mean** the arithmetical average of all the individual scores (or values) in a set of scores **measure of central tendency** a score that indicates the central or average value of a set of scores; see also *mean*, *median*, *mode* **measure of variability** a statistic that indicates how widely scores (or values) are distributed or scattered around the central point **median** the middle score (or mid-point) of a set of scores (or values) **mode** the most frequently occurring score (or value) in a set of scores **conclusion** in relation to research, a decision about what the results obtained from a research study mean **generalisation** in research, a decision about how widely the findings of an investigation can be applied, particularly to other members of the population from which the sample was drawn **accuracy** The accuracy of a measurement relates to how close it is to the true value of the quantity being measured. Accuracy is not quantifiable; measurement values may be described as more accurate or less accurate. **precision** Refers to how closely a set of measurement values agree with each other. Precision gives no indication of how close the measurements are to the true value and is therefore a separate consideration to accuracy. **true value** The value, or range of values, that would be found if the quantity could be measured perfectly. **validity** the extent to which a measure accurately measures what it is supposed to be measuring; see also *internal validity* and *external validity* **external validity** the extent to which the results obtained for a study can be applied beyond the sample that generated them, specifically to individuals in a different setting and over time; compare with *internal validity* **internal validity** the extent to which an investigation actually investigated what it set out to investigate and/or claims to have investigated; compare with *external validity* **reliability** the extent to which a measure produces results that are consistent, dependable and stable **repeatability** the degree to which a specific research investigation obtains similar results when it is conducted again under the same conditions on all occasions **reproducibility** how close the results are to each other when an investigation is replicated under changed conditions