A good limitation names what the method could not capture and says how that might change the conclusion. It never adds events you did not observe.
This lesson is part of geographical investigation. The wider planning lives in designing a small ethical geographical investigation, so this page only covers the limitation paragraph.
How is a limitation different from the conclusion?
The conclusion says what your data shows. The limitation says how far that statement can be trusted. Writing both in one blur makes each one weaker.
A useful limitation has three parts: what the method did, what that leaves out, and what effect this could have on the conclusion.
Worked example: litter counts on one afternoon
This is a worked example. A pair of students counted pieces of litter along three 20 m stretches of a school field edge. They counted for 10 minutes each on one Tuesday afternoon.
| Stretch | Litter pieces counted |
|---|---|
| A, near the canteen | 27 |
| B, middle of the field edge | 12 |
| C, near the gate | 9 |
The data supports one statement: stretch A had the most litter on that afternoon, 27 pieces compared with 12 and 9. The total is 27 + 12 + 9 = 48, so A held 27 ÷ 48 = 56.25%, about 56%, of the counted pieces.
Now write each limitation as three parts.
- Time. “The counts were taken on one afternoon only (what was done), so days with a different canteen schedule are not represented (what it leaves out). The pattern at A may be weaker or stronger on other days.”
- Sample. “Only three stretches of 20 m were counted (what was done), so the rest of the field edge is unknown (what it leaves out). Stretch A may not represent other places near buildings.”
The mistake: inventing what you did not see
A tempting sentence is: “The litter at A was higher because it rained the day before and washed rubbish there.” The students did not record rain, so this is an invented observation.
| Invented claim | Honest limitation |
|---|---|
| “It rained the day before, which moved the litter.” | “Weather was not recorded, so its effect on the counts cannot be judged.” |
| “Everyone at school drops litter near the canteen.” | “Only litter pieces were counted, so the reasons for the pattern are not shown by this data.” |
| “Counts would be the same every day.” | “One afternoon was counted, so the result may change on other days.” |
The honest version loses nothing. It shows the marker that you know the edge of your own evidence.
Check yourself
A student measured soil temperature at two spots, one under a tree and one on open grass, at 10.00 a.m. on one day. The readings were 26 °C and 31 °C. Write one limitation using the three-part pattern.
Answer
One model answer: “Temperature was read once at each spot at 10.00 a.m. on one day (what was done), so changes across the day and on other days are not shown (what it leaves out). The gap of 5 °C may be larger or smaller at other times.”
The difference is 31 − 26 = 5 °C. The limitation does not say why the open grass was hotter, because no sun or cloud data was recorded.
What to study next
To see how the data itself should be shown before you comment on it, read presenting data clearly. Then try the geographical investigation practice set.
For help with a real investigation write-up from your own school, see online one-to-one Geography tuition.