Term
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Definition
| An accurate measurement is one in which the mean (average) of repeated readings is close to what we know is the true value. |
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| Marking a scale on a measuring instrument |
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Definition
| Your measurements; the results of your experiments
The plural of datum |
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Definition
| Random errors cause your readings to be spread about the true value. We can compensate for random errors by taking a large number of readings and find the mean (average) of them. |
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Definition
| Affect all of your results. You cannot compensate for them by taking an average of lots of readings. Your results will be inaccurate and will not be the same as the true value. |
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Definition
| These are caused by measuring instruments that have a false zero. It may affect all your results. It makes your results inaccurate. |
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Definition
| Data which has been checked so it can be judged whether reliable or not. |
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Term
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Definition
| A series of experiments in which all the variables have been controlled except the variable that is being tested. |
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| Your results and the repeats are very close together. |
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Definition
| Your results are reliable if other people get the same results as you. |
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Definition
| Your results are valid if you are measuring the actual thing you want to measure AND your results are accurate. |
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Term
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Definition
| A categoric variable is one best described by a label (usually a word) eg eye colour is a categoric variable – blue or brown. |
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Definition
| A continuous variable is one we measure, it can have any numerical value. eg temperature 37.6°C and 45.2°C |
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Definition
| A control variable is one which could affect our result but does not because we have kept it the same in all our experiments. |
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Term
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Definition
| The dependent variable is the one we measure each time we change the independent variable. It is the result of our experiment. We plot it on the y-axis of a graph. |
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Term
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Definition
| A variable which can only have whole numbers. The number of leaves on a plant is a discrete variable. |
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Term
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Definition
| These are categoric variables that can be ranked (put into order) e.g. large, medium or small. |
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Definition
| This is the variable that we change (or choose) in our investigation. We plot it on the x-axis of a graph. |
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