| A | B |
|---|
| Accuracy | measurement is accurate if close to the true value |
| Interval | quantity between readings .eg 10cm, 20 cm , 30 cm has 10cm interval |
| Precison | precise measurements have little spread about the mean (close to each other). Does noy mean they are close to the true value however! |
| Range | the max & minimum values of the measured variables |
| Repeatable | repeatable measurement if the original experimenter (You)repeats the investigation using the same equip & method & the same results are obtained |
| Reproducible | - if the investigation is repeated by another person, or using different equip or method & the same results are obtained |
| Resolution | The smallest change in the quantity being measured by an instrument that gives a perceptible change in the reading (i.e a difference) |
| Independent variable | the values are changed/selected by the person doing the experiment ( You!) |
| Dependent variable | the value that is measured each time you change the the value of the independent variable |
| Control variable | Other factors that could affect an experiment and need to be controlled ! (ideally not changing) |
| Categoric variable | have names ! (shown in bar charts) |
| Continuous variables | have values& units (go up in numbers,- shown in line graphs) |
| True value | the value obtained if perfectly measured |
| Valid conclusion | conclusion supported by data from a well done experiment |
| Validity | suitability of the experiment e,g invalid if control variable are not controlled ! |
| Uncertainity | the interval in which the true value is likely to be , with a given level of confidence.e.g my mass 50Kg +/- 5Kg |
| Sketch graph | line graph (not graph paper) that shows generally relationship between variable. Label axis |
| Measurement error | difference between a measured value and the true value |
| anomalies | results which are judged to be outside the variation that may be expected by random error |
| random error | results may not be exact true value. Taking more readings to get a mean reduces their effect |
| systematic error | results are consistently different from the true value due to experimental/equipment issues |
| calibration | ensuring measuring device reads correctly |
| fair test | only the independent variable (the thing you are changing) affects the dependent variable |
| Hypothesis | a proposal intended to explain certian facts or observations |
