{"id":"study-hypotheses-practice-set","audience":"college","category":"studying","technique":"grounding","track":"study","title":"Practice writing null and alternative hypotheses","free":false,"task":"Your Stats quiz asks you to write hypotheses for study descriptions. You want exactly 4 numbered practice scenarios, then all answers together under an 'Answers' line, each answer in the form 'H0: ... | Ha: ...' using the symbols from your notes, plain text. Include at least one two-sided test, and follow your professor's correction about which symbol goes in the null.","materialLabel":"Your stats notes (attached to your prompt automatically)","material":"STAT 2100 - Lecture 15 - Hypothesis tests (Prof. Nakamura)\n\nH0 = null hypothesis: \"no effect / no difference / status quo\"\nHa = alternative hypothesis: what the researcher suspects\n\nSymbols we use: μ (population mean), p (population proportion)\n\nWriting Ha:\n- \"greater than\" / \"increased\" -> Ha: μ > value (one-sided)\n- \"less than\" / \"decreased\" -> Ha: μ < value (one-sided)\n- \"different from\" / \"changed\" -> Ha: μ ≠ value (TWO-sided)\n\nH0: I wrote \"H0 uses < or > to match Ha.\"\n** Prof. N correction: NO. H0 ALWAYS uses = . Example: H0: μ = 30 | Ha: μ > 30 **\n\nHypotheses are about POPULATION parameters (μ, p), never sample stats (x̄, p̂). \"If you write x̄ in a hypothesis, it's automatically wrong.\"\n\nExample from class: A coffee shop claims its mean wait time is 4 minutes. A customer thinks it's longer. -> H0: μ = 4 | Ha: μ > 4\n\nQuiz Friday: 5 scenarios, write H0 and Ha.\nNot on this quiz: p-values, test statistics (next week).","rules":[{"type":"questionCount","count":4},{"type":"plainText"}],"mistakes":[{"title":"Not saying how many scenarios","why":"The AI picks its own number, and it usually picks more scenarios than you need.","fix":"Be exact: \"Exactly 4 numbered scenarios.\"","checks":["questionCount"]},{"title":"Missing the correction","why":"Your notes still contain the wrong rule about H0 next to the fix.","fix":"Add: \"H0 always uses =, per my professor's correction.\"","checks":["r0"]},{"title":"Only one-sided cases","why":"The AI tends to write 'greater than' scenarios and skip the two-sided ones.","fix":"Add: \"At least one two-sided test.\"","checks":["r1"]},{"title":"Answers under each scenario","why":"Seeing the answer right away means you never test yourself.","fix":"Add: \"Put all answers at the end under 'Answers', like 'H0: μ = 4 | Ha: μ > 4'.\"","checks":["r2"]},{"title":"Forgetting where it will be read","why":"AI formats for a screen, with bold and headings that show up as stray symbols on a printed page.","fix":"Say: \"Plain text, no bold, no headings.\"","checks":["plainText"]}],"promptHints":[{"label":"Says how many scenarios","patterns":["\\b(4|four)\\b.{0,25}scenario"]},{"label":"Asks for a two-sided case","patterns":["two.sided","≠","different"]},{"label":"Shows the answer shape","patterns":["H0:.{0,20}Ha:","\\|"]},{"label":"Puts answers at the end","patterns":["answers?.{0,30}(end|bottom|after|separate)","(end|bottom).{0,20}answers?"]},{"label":"Says to use only the material","patterns":["only.{0,30}(notes|material|source|excerpt|text|reading|passage|draft|facts|article|handout|sheet|guide|chapter|data|list)","no outside","don't add","do not add","don't invent","correct","always uses ="]}],"hint":"Practice should match how your quiz grades. Show the AI the exact answer shape, ask for a two-sided case, say where answers go, and point it to the H0 correction.","rubricLabels":["Every answer is in the form 'H0: ... | Ha: ...', uses = in H0 (the correction), and uses only population symbols (μ or p), never x̄ or p̂","At least one scenario calls for a two-sided test, and its Ha uses ≠","All answers appear together after the last scenario under an 'Answers' line, each correct for its scenario, with no p-values or test statistics"]}