// Numbas version: finer_feedback_settings
{"name": "Are described variables from Poisson or binomial distributions?, ", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"variable_groups": [], "variables": {"mm": {"group": "Ungrouped variables", "templateType": "anything", "definition": "[[1,-1],[1-2*t,2*t-1],[-1,1]]", "name": "mm", "description": ""}, "p2": {"group": "Ungrouped variables", "templateType": "anything", "definition": "switch(t=0,random(0..abs(b)-1 except p1),random(0..abs(pd)-1 except p3))", "name": "p2", "description": ""}, "b": {"group": "Ungrouped variables", "templateType": "anything", "definition": "\n[\"20% of eggs from a family-run farm are bad. X is the number of bad eggs in a box of a dozen.\",\n  \"A salesperson has a 50% chance of making a sale on a customer visit and she arranges 10 visits in a day. Let X be the number of sales that day.\",\n  \"30% of items off a factory production line have been shown to have defects. Let A be the number of defectives in a box of 20 such items.\",\n  \"One in ten new small businesses in the north-east goes bust within a year. Let X be the number of small businesses that fail in the next year out of thirty that have been set up.\",\n  \"The probability that an office photocopier will fail on any given day is 0.15. The human resources office at Newcastle University has ten such photocopiers; Let Y be the number of photocopiers that fail today.\",\n  \"Callers to the Vodaphone call centre will get through to an operator immediately with probability 0.25. X is the number of callers that speak to an operator immediately out of thirty such callers.\",\n  \"Experience has shown that two in every ten components produced by a circuitboard company will be defective. A random sample of 100 components is inspected for defects, and D is the number of defectives in this sample.\"]\n", "name": "b", "description": ""}, "ch1": {"group": "Ungrouped variables", "templateType": "anything", "definition": "b[p1]", "name": "ch1", "description": ""}, "p1": {"group": "Ungrouped variables", "templateType": "anything", "definition": "random(0..abs(b)-1)", "name": "p1", "description": ""}, "ch2": {"group": "Ungrouped variables", "templateType": "anything", "definition": "switch(t=0,b[p2],pd[p2])", "name": "ch2", "description": ""}, "p3": {"group": "Ungrouped variables", "templateType": "anything", "definition": "random(0..abs(pd)-1)", "name": "p3", "description": ""}, "pd": {"group": "Ungrouped variables", "templateType": "anything", "definition": "\n[\"Y is the number of flights sold per hour by an online travel agency. This travel agency usually sells 10 flights per hour.\",\n  \"X is the number of cars sold by a local garage in a month. This garage usually sells about 10 cars per month.\",\n  \"The number of calls, Y, received at the British Passport Office in Durham occurs at the rate of 10 a minute.\",\n  \"We are interested in X, the number of machine breakdowns in a day. Such breakdowns at a particular IT company occur at a rate of eight per week.\",\n  \"X is the number of e-mails arriving in your inbox in a one hour period.  On average you receive 3 e-mails per hour.\",\n  \"On average, three patients arrive at a local Accident and Emergency department every hour. We count the number, X, of patients in an hour period.\",\n  \"About five customers arrive at a fish shop queue every ten minutes during the lunch time rush. We count X, the number of customers arriving during the lunch time rush.\"]\n", "name": "pd", "description": ""}, "t": {"group": "Ungrouped variables", "templateType": "anything", "definition": "random(0,1)", "name": "t", "description": ""}, "ch3": {"group": "Ungrouped variables", "templateType": "anything", "definition": "pd[p3]", "name": "ch3", "description": ""}}, "ungrouped_variables": ["p2", "p3", "b", "mm", "ch3", "ch1", "ch2", "p1", "t", "pd"], "rulesets": {}, "name": "Are described variables from Poisson or binomial distributions?, ", "showQuestionGroupNames": false, "functions": {}, "parts": [{"displayType": "radiogroup", "layout": {"type": "all", "expression": ""}, "choices": ["{ch1}", "{ch2}", "{ch3}"], "matrix": "mm", "type": "m_n_x", "maxAnswers": 0, "shuffleChoices": true, "marks": 0, "scripts": {}, "maxMarks": 0, "minAnswers": 0, "minMarks": 0, "shuffleAnswers": false, "showCorrectAnswer": true, "answers": ["Binomial Distribution", "Poisson Distribution"], "warningType": "none"}], "variablesTest": {"condition": "", "maxRuns": 100}, "statement": "\n  <p>Which of the following random variables could be modelled with a binomial distribution and which could be modelled with a Poisson distribution?</p>\n<p>You will lose 1 mark for every incorrect answer. The minimum mark is 0.</p>\n  ", "tags": ["checked2015", "MAS1403", "MAS1604"], "question_groups": [{"pickingStrategy": "all-ordered", "questions": [], "name": "", "pickQuestions": 0}], "preamble": {"css": "", "js": ""}, "type": "question", "metadata": {"notes": "<p><strong>06/12/2013</strong></p>\n<p>Replaced a Poisson scenario that wasn't strictly Poisson. (AJY)</p>\n<p><strong>31/12/2012:</strong></p>\n<p><strong><br /></strong>Checked choices, OK. Added tag sc as examples can be easily added to via the arrays b and pd.</p>", "licence": "Creative Commons Attribution 4.0 International", "description": "<p>Given descriptions of &nbsp;3 random variables, decide whether or not each is from a Poisson or Binomial distribution.</p>"}, "advice": "<p>No solution given.</p>", "contributors": [{"name": "Newcastle University Mathematics and Statistics", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/697/"}]}]}], "contributors": [{"name": "Newcastle University Mathematics and Statistics", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/697/"}]}