--- title: "Judging a Political Claim" description: "Campaigns use numbers to persuade. Official statistics can help check those claims. Examine the source, baseline, denominator and time window, and ask what assumptions sit behind a costed promise." canonical: https://lightmysky.com/learn/civics-and-economics/judging-a-political-claim-mt_pGwJVkz8L1 source: https://lightmysky.com/learn/civics-and-economics/judging-a-political-claim-mt_pGwJVkz8L1.md retrieved: 2026-11-12 --- > **Agent view.** This is the Markdown twin of the page, for tools and assistants. > When to use this site, and the call that answers each job: https://lightmysky.com/agent-instructions.md > API description (OpenAPI 3.1): https://lightmysky.com/openapi.json · Authentication: https://lightmysky.com/auth.md > Pricing: https://lightmysky.com/pricing.md · Catalog: https://lightmysky.com/llms.txt · Full catalog: https://lightmysky.com/llms-full.txt > Every machine-readable file on this domain: https://lightmysky.com/.well-known/ai-catalog.json > Ask for Markdown with `Accept: text/markdown`, a `.md` address, or `?mode=agent`. # Judging a Political Claim Campaigns use numbers to persuade. Official statistics can help check those claims. Examine the source, baseline, denominator and time window, and ask what assumptions sit behind a costed promise. Subject: Civics & Economics · Area: Government · Ages 16 to 18 Page: https://lightmysky.com/learn/civics-and-economics/judging-a-political-claim-mt_pGwJVkz8L1 ## Ready when they can - Take a political statistic and identify its baseline, denominator and time window - Explain how the same policy can be reported as a cut and as an increase - Say what you would need to know before believing a costed promise ## Lesson: Read the number behind the number You have compared policies and their costs. A political claim needs an evidence check too. A statistic can support a claim when its source and meaning fit the question. If bus use rises after fares are removed, that shows changed use. It does not establish that free fares caused the rise. Changes to routes or working hours could also matter. Find the baseline, the comparison value, and the dates covered. A rate's denominator is the group or total at the bottom of the fraction. For unemployment, divide unemployed people by the labour force. Percent means out of 100. Multiply the ratio by 100 to find the number before the % sign. Here, 12 ÷ 200 = 0.06 = 6%, since 0.06 × 100 = 6. Later, 10 ÷ 125 = 0.08 = 8%, since 0.08 × 100 = 8. The count fell, but the rate rose. Check that the definitions match. **Example.** A fictional service receives £40 million in Year 1, £55 million in Year 2 and £50 million in Year 3. Year 3 is £10 million above Year 1, but £5 million below Year 2. It is an increase against one baseline and a cut against the other. Both comparisons need their baseline stated. These cash amounts do not by themselves show what the money buys after prices change. *(drawing: Year 3 is above Year 1 and below Year 2. All amounts are in millions of pounds.)* For a poll, identify whom it aims to describe and how people were recruited. Asking passers-by at one shopping centre is convenience sampling; it may miss other groups. More interviews there do not remove that selection problem. A poll of eligible voters can describe that group. To forecast an election, researchers estimate who is likely to vote. They cannot know future turnout for certain. Trace a campaign figure to its original release or dataset. Check the dates, population, units and definitions. Official statistics agencies publish methods; other sources need checking too. Two unemployment figures may use different measures. Read the notes before comparing them. Agencies can revise figures or methods openly. A change does not, by itself, show deception. For a costed promise, multiply the number served by the cost per person, then check for omitted expenses. Ask whether the total is annual or one-off, whether the inputs are realistic, how prices may change and where funding comes from. For example, 300 places at £400 each cost £120,000 before extra expenses. Correct multiplication does not prove that the estimate or funding is sound. *(drawing: A cost estimate needs a calculation and a check of its assumptions.)* **Recap.** Check the source, baseline, denominator and dates. For a promise, check costs and funding. Separate what a number shows from what a speaker says caused it. *Lesson, questions and flashcards written for this dataset. The numerical budgets and training-place estimates are fictional teaching examples.* ## Practice 8 questions on this page, each with its working shown. ## Needs first - [Public policy and public problems](https://lightmysky.com/learn/civics-and-economics/public-policy-and-public-problems-mt_5vYuvjkprY) ## Optional connections - [What a feed is optimised for](https://lightmysky.com/learn/personal-and-social-development/what-a-feed-is-optimised-for-mt_kzhPakduam) - [Where International Rules Come From](https://lightmysky.com/learn/civics-and-economics/where-international-rules-come-from-mt_prBdcYuLoY)