A reliable case study fact carries a source, a date, a place and a scope. If any of the four is missing, the fact is not ready to use.
This page shows a short checking routine with an invented case. No real place, statistic or source is used.
What does the mistake look like?
A student builds a case file from the first page of search results. A blog post says “City Q has grown rapidly”. The student copies the sentence, adds a number from a second site and writes the case as fact.
Later the question asks for an impact in a specific year. The student cannot say where the number came from, which year it describes or whether the city boundary meant the same thing in both sources.
What causes it?
Search results reward popular pages, not original evidence. A summary page may quote a figure with no date, and a later page may copy it. Case facts that look consistent can all trace back to one unchecked source.
Geographic facts also shift. A population, a rate or a management plan can change, so a fact that was right once may not describe the present.
Worked example
Invented case: City Q and a claim that “the population grew by 3%”.
Step 1, ask four questions. Which source? Which years? Which place boundary? What exactly was measured?
Step 2, trace to the original. The blog post links to a report from the invented “Q Statistics Office”. The report gives a population of 200,000 in one year and 206,000 five years later, for the city council area.
Step 3, check the arithmetic. The increase is 206,000 − 200,000 = 6,000. As a percentage, 6,000 ÷ 200,000 = 0.03, which is 3%. So the blog’s 3% is correct for that five-year period, and the period was missing from the blog.
Step 4, write a ledger entry.
| Field | Entry |
|---|---|
| Verified fact | Population 200,000 to 206,000 over five years, city council area |
| Source and date | Q Statistics Office report, year shown on the report |
| Interpretation | Growth of 3% over five years, about 0.6% a year |
| Open question | Is the boundary the same at both dates? |
The yearly figure is 3 ÷ 5 = 0.6, a simple average that ignores compounding. The entry labels it as an interpretation, not a verified fact.
Step 5, use the entry. An answer can now say: “Over five years the population of the council area rose from 200,000 to 206,000, about 3%, according to the statistics office.” That sentence includes the source, the scope and the period.
A ledger that keeps fact and opinion apart
The Geography evidence and case-study ledger asks for a source reference, date, place and the fact you selected.
It separates verified fact, interpretation and unanswered question, and flags a statistic with no year as incomplete. It never invents case facts, and it does not give political verdicts. The statistics and distribution explorer helps with summary numbers such as means and ranges.
If a source states an opinion, such as whether a policy worked, record it as a viewpoint with the name of the source. Do not write it as a fact.
Check yourself
1. A note says “Flooding cost 5 billion” with no year, place or currency. What is missing?
Show answer
The year, the place, the currency, what was counted and the source. As written it cannot be used, and the ledger would mark it incomplete.
2. A population grew from 500,000 to 525,000. Find the percentage increase.
Show answer
Increase 525,000 − 500,000 = 25,000. 25,000 ÷ 500,000 = 0.05, so 5%.
3. A report says a new flood barrier “was clearly a success”. Is this a fact or an interpretation?
Show answer
It is an interpretation, since “success” depends on the measure used. Record the claim with its source, then look for measured evidence such as flood depth before and after.
Where to go next
Build reasoning with case-study reasoning, and see the clinic on memorising a case without linking it to the task for how to use checked facts. The Geography learning guide lists the cases you may need across topics.
If your case files still feel shaky, a teacher can review them with you. See online one-to-one Geography tuition.