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After collecting data, you present, analyse and evaluate it
You have planned your enquiry and collected your data. The last four enquiry strands are about what you do with it. In order, they are: selecting ways of processing and presenting data (strand 3), describing, analysing and explaining data (strand 4), reaching conclusions (strand 5) and evaluating the enquiry (strand 6).
In the exam you may get fieldwork from a place you have never seen, or questions on your own enquiry. The skills are the same for both. To show them, we will use one made-up enquiry: Does ground plant cover fall as you move deeper into a woodland? Six sites were measured along a line into the wood, 10 m apart.
Raw numbers in a table are hard to read. Presenting them turns them into something you can see. A range of visual (photos, annotated sketches), graphical (bar charts, line graphs, scatter graphs, pie charts) and cartographic (map-based) methods is available. The choice should fit the data.
We want to know if two things are linked, such as distance into the wood and plant cover, so a scatter graph suits. To show how something changes along a route, a line graph works. To show a pattern across a place, put results on a map.
Adapting means changing a method so it fits your data better. For example: put located bar charts on a sketch map, annotate a photo with your measurements, or choose a scale that spreads out the points.
Key terms:
Graph types are covered in detail in the lessons on Graphs and Charts, so here the skill is the choice and the justification. Always say why: "I used a scatter graph because I wanted to see if two sets of data were linked" earns marks.
These are three different jobs, and examiners mark them separately.
One data set rarely tells the whole story. In our enquiry, light level also falls with distance (80% to 20%). Both fall together, which supports the idea that plant cover drops because there is less light. Establishing links between data sets makes your explanation stronger.
Use simple statistics to make results clearer. The mean, median and range summarise a data set, and a line of best fit on a scatter graph shows the trend. The calculations are taught in the lessons on Averages, Range and Quartiles and on Percentages, Trends and Misleading Data.
An anomaly is a result that does not fit the pattern. Site 5 is the anomaly: 60% plant cover, when its neighbours are 36% and 15%. You must identify it, then suggest a reason, for example the quadrat landed in a gap left by a fallen tree. Do not just delete it. Mention it, explain it, and say how it affects your results.
Describe the pattern in plant cover. Answer: "Plant cover generally falls with distance into the wood, from 70% at site 1 to 15% at site 6. The one exception is site 5 (60%), which is an anomaly because it is far higher than the sites either side." That uses figures and names the anomaly.
A conclusion answers the original enquiry question
A conclusion answers your original question or hypothesis, using your results as evidence. It must link back to your aims. A good conclusion has three parts:
Be honest about how far your data goes. "Mostly supported" or "partly supported" is better than a bold claim your six sites cannot prove.
Writing a conclusion that is not about the question you asked. Giving an answer with no figures. Ignoring anomalies. Saying a hypothesis is "proved" when you only had a few results.
Evaluation means judging how good your enquiry was. The spec points to four things.
What went wrong in collecting data? Perhaps different students judged plant cover in different ways, or the quadrat was placed by eye. Say how you would fix it.
What does the data fail to show? Six sites on one day, in one season, may not represent the whole wood.
What else would help? Measurements of soil moisture, a second visit in another season, or secondary data on the weather.
How far can you trust them? More sites and repeat readings make them more reliable.
Key terms:
Evaluate with a simple pattern: problem, effect, improvement. "Only six sites were measured (problem), so one anomaly could change the pattern (effect). Measuring 15 sites would give more reliable results (improvement)."
Writing "it was too hot" or "we ran out of time" with no link to the data. A problem only earns marks when you say what it did to the results and how you would improve it.
A student measured plant cover at six sites into a woodland and found one result far higher than the rest. (a) Describe what is meant by an anomaly. [1 mark] (b) Suggest one reason the anomaly might have happened. [1 mark] (c) Explain one way the student could make the conclusion more reliable. [2 marks]
(a) A result that does not fit the pattern of the other results. (1)
(b) The quadrat was placed in a gap left by a fallen tree, so more light reached the plants. (1)
(c) Measure more sites or repeat each reading (1), then use the mean, so one odd result has less effect on the conclusion (1).
For a 2 mark "explain" question, give the improvement and then say what it fixes. The second mark is for the effect on reliability.