// Numbas version: exam_results_page_options
{"name": "CorrelationInference-Couples", "extensions": ["stats"], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"name": "CorrelationInference-Couples", "tags": [], "metadata": {"description": "<p>Calculate the Pearson correlation coefficient and conduct a hypothesis test.</p>", "licence": "Creative Commons Attribution-ShareAlike 4.0 International"}, "statement": "<p>It is well known that similarity in attitudes, beliefs and interests plays an important role in interpersonal attraction. A researcher developed a questionnaire which was completed by 8 married couples. One question sought to place each individual on a 20 point scale in which low scores represent liberal attitudes and high scores represent conservative attitudes. The data were:</p>\n<table border=\"0\" cellpadding=\"0\" cellspacing=\"0\" style=\"border-collapse: collapse; width: 314px;\"><colgroup><col width=\"64\" span=\"3\" style=\"width: 48pt;\"/> </colgroup>\n<tbody>\n<tr height=\"20\" style=\"height: 15.0pt;\">\n<td height=\"20\" style=\"height: 15pt; width: 62px;\">Couple</td>\n<td style=\"width: 98px;\">Wife $(x)$</td>\n<td style=\"width: 111px;\">Husband $(y)$</td>\n</tr>\n<tr height=\"20\" style=\"height: 15.0pt;\">\n<td height=\"20\" style=\"height: 15pt; text-align: center; width: 62px;\">{obj[0]}</td>\n<td style=\"padding-bottom: 4px; padding-top: 4px; width: 98px;\">{r1[0]}</td>\n<td style=\"padding-bottom: 4px; padding-top: 4px; width: 111px;\">{r2[0]}</td>\n</tr>\n<tr height=\"20\" style=\"height: 15.0pt;\">\n<td height=\"20\" style=\"height: 15pt; text-align: center; width: 62px;\">{obj[1]}</td>\n<td style=\"padding-bottom: 4px; padding-top: 4px; width: 98px;\">{r1[1]}</td>\n<td style=\"padding-bottom: 4px; padding-top: 4px; width: 111px;\">{r2[1]}</td>\n</tr>\n<tr height=\"20\" style=\"height: 15.0pt;\">\n<td height=\"20\" style=\"height: 15pt; text-align: center; width: 62px;\">{obj[2]}</td>\n<td style=\"padding-bottom: 4px; padding-top: 4px; width: 98px;\">{r1[2]}</td>\n<td style=\"padding-bottom: 4px; padding-top: 4px; width: 111px;\">{r2[2]}</td>\n</tr>\n<tr height=\"20\" style=\"height: 15.0pt;\">\n<td height=\"20\" style=\"height: 15pt; text-align: center; width: 62px;\">{obj[3]}</td>\n<td style=\"padding-bottom: 4px; padding-top: 4px; width: 98px;\">{r1[3]}</td>\n<td style=\"padding-bottom: 4px; padding-top: 4px; width: 111px;\">{r2[3]}</td>\n</tr>\n<tr height=\"20\" style=\"height: 15.0pt;\">\n<td height=\"20\" style=\"height: 15pt; text-align: center; width: 62px;\">{obj[4]}</td>\n<td style=\"padding-bottom: 4px; padding-top: 4px; width: 98px;\">{r1[4]}</td>\n<td style=\"padding-bottom: 4px; padding-top: 4px; width: 111px;\">{r2[4]}</td>\n</tr>\n<tr height=\"20\" style=\"height: 15.0pt;\">\n<td height=\"20\" style=\"height: 15pt; text-align: center; width: 62px;\">{obj[5]}</td>\n<td style=\"padding-bottom: 4px; padding-top: 4px; width: 98px;\">{r1[5]}</td>\n<td style=\"padding-bottom: 4px; padding-top: 4px; width: 111px;\">{r2[5]}</td>\n</tr>\n<tr height=\"20\" style=\"height: 15.0pt;\">\n<td height=\"20\" style=\"height: 15pt; text-align: center; width: 62px;\">{obj[6]}</td>\n<td style=\"padding-bottom: 4px; padding-top: 4px; width: 98px;\">{r1[6]}</td>\n<td style=\"padding-bottom: 4px; padding-top: 4px; width: 111px;\">{r2[6]}</td>\n</tr>\n<tr height=\"20\" style=\"height: 15.0pt;\">\n<td height=\"20\" style=\"height: 15pt; text-align: center; width: 62px;\">{obj[7]}</td>\n<td style=\"padding-bottom: 4px; padding-top: 4px; width: 98px;\">{r1[7]}</td>\n<td style=\"padding-bottom: 4px; padding-top: 4px; width: 111px;\">{r2[7]}</td>\n</tr>\n</tbody>\n</table>\n<div id=\"statement-input\" disabled=\"disabled\" data-bind=\"writemaths: statement, tinymce_plugins: ['jmevisible','preview'], variableReferrer: {value: statement, description: 'Statement', kind: 'html'}\">\n<p>Null hypothesis $H_0$: There is no association between the attitudes of wives and husbands.</p>\n</div>\n<p class=\"help-block\">Use statistics software to answer the following questions.</p>", "advice": "<p>Conduct a regression analysys using statistics software - e.g., in Minitab, use Stat | Regression | Fitted Line Plot.</p>", "rulesets": {"std": ["all", "fractionNumbers", "!collectNumbers", "!noLeadingMinus"]}, "extensions": ["stats"], "variables": {"rr1": {"name": "rr1", "group": "Ungrouped variables", "definition": "rk(r1)", "description": "", "templateType": "anything"}, "tol": {"name": "tol", "group": "Ungrouped variables", "definition": "0.05", "description": "", "templateType": "anything"}, "r1": {"name": "r1", "group": "Ungrouped variables", "definition": "darr(n,m,[random(1..20)])", "description": "", "templateType": "anything"}, "spxy": {"name": "spxy", "group": 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