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{"name": "True/false statements about confidence intervals - Marijuana study", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"name": "True/false statements about confidence intervals - Marijuana study", "tags": [], "metadata": {"description": "<p>Multiple response question (3 correct out of 6). Selection of questions from a pool. Real data from a YouGov survey.</p>", "licence": "Creative Commons Attribution-ShareAlike 4.0 International"}, "statement": "<p>In a 2015 survey, 1598 UK adults were asked: \"Do you think the use of marijuana should be legalized?\" 32% of the respondents said it should.</p>\n<p>The standard error&nbsp;for this estimate was 1.2%. The 95% confidence&nbsp;interval (CI) was: (29.7%, 34.3%).</p>\n<p>Identify each of the following statements as true or false (note that every correct answer is worth 1 mark, but every wrong answer loses a mark).</p>", "advice": "<p>Check the literature on Confidence Intervals (e.g., Chapter 5 in&nbsp;<a href=\"https://www.openintro.org/book/os/\">OpenIntro Statistics</a>).</p>", "rulesets": {"std": ["all", "fractionNumbers", "!collectNumbers", "!noLeadingMinus"]}, "extensions": [], "variables": {"statements": {"name": "statements", "group": "Statements", "definition": "t_statements+f_statements", "description": "", "templateType": "anything"}, "t_statements": {"name": "t_statements", "group": "Statements", "definition": "[ safe(\"The percentage of UK adults who think marijuana should be legalised may be outside the CI.\"), safe(\"A 99% CI constructed using the same sample would be larger than the reported 95% CI.\"), safe(\"We can be 95% confident that the percentage of UK adults who think marijuana should be legalised is between 29.7% and 34.3%. \"), safe(\"There is statistically significant evidence (at the $\\\\alpha=0.05$ level) that the percentage of UK adults who think marijuana should be legalised is above 25%.\"), safe(\"If we repeated this study 1000 times (using 1000 different samples) and constructed a 95% CI each time, then approximately 50 of those 1000 CIs would $not$ contain the true percentage of UK adults who think marijuana should be legalised.\"), safe(\"If we repeated this study 1000 times (using 1000 different samples) and constructed a 95% CI each time, then approximately 950 of those 1000 CIs would contain the true percentage of UK adults who think marijuana should be legalised.\"), safe(\"A 90% CI constructed using the same sample would be smaller than the reported 95% CI.\") ]", "description": "", "templateType": "list of strings"}, "f_statements": {"name": "f_statements", "group": "Statements", "definition": "[ safe(\"A 99% CI constructed 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