// Numbas version: exam_results_page_options
{"name": "Charlie's copy of Perform a paired t-test", "extensions": ["stats"], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"statement": "<p>The following data was obtained from <strong>right-handed</strong> participants.</p>\n<p>The observations consist of the time taken in seconds for each participant to complete a&nbsp;reaction time task by firstly using their right hand and secondly using their left hand.</p>\n<p>Carry out a paired t-test to test whether there is evidence of a difference in the&nbsp;reaction times.</p>\n<p>Use SPSS to complete this question. Save your output in the answer box.</p>\n<p></p>\n<table>\n<tbody>\n<tr style=\"height: 17px;\">\n<td style=\"height: 17px;\">Subject</td>\n<td style=\"height: 17px;\">Reaction Time (Right Hand) (seconds)</td>\n<td style=\"height: 17px;\">Reaction Time (Left Hand) (seconds)</td>\n</tr>\n<tr style=\"height: 17px;\">\n<td style=\"height: 17px;\">1</td>\n<td style=\"height: 17px;\">1:02</td>\n<td style=\"height: 17px;\">2:11</td>\n</tr>\n<tr style=\"height: 17px;\">\n<td style=\"height: 17px;\">2</td>\n<td style=\"height: 17px;\">2:33</td>\n<td style=\"height: 17px;\">2:23</td>\n</tr>\n<tr style=\"height: 9px;\">\n<td style=\"height: 9px;\">3</td>\n<td style=\"height: 9px;\">1:45</td>\n<td style=\"height: 9px;\">1:56</td>\n</tr>\n<tr style=\"height: 17px;\">\n<td style=\"height: 17px;\">4</td>\n<td style=\"height: 17px;\">1:59</td>\n<td style=\"height: 17px;\">2:15</td>\n</tr>\n<tr style=\"height: 17px;\">\n<td style=\"height: 17px;\">5</td>\n<td style=\"height: 17px;\">2:56</td>\n<td style=\"height: 17px;\">3:07</td>\n</tr>\n<tr style=\"height: 17px;\">\n<td style=\"height: 17px;\">6</td>\n<td style=\"height: 17px;\">2:44</td>\n<td style=\"height: 17px;\">2:55</td>\n</tr>\n<tr style=\"height: 17px;\">\n<td style=\"height: 17px;\">7</td>\n<td style=\"height: 17px;\">3:14</td>\n<td style=\"height: 17px;\">3:32</td>\n</tr>\n<tr style=\"height: 17px;\">\n<td style=\"height: 17px;\">8</td>\n<td style=\"height: 17px;\">2:01</td>\n<td style=\"height: 17px;\">1:54</td>\n</tr>\n</tbody>\n</table>\n<p></p>", "advice": "", "metadata": {"licence": "Creative Commons Attribution 4.0 International", "description": "<p>Paired t-test to see if there is a difference between times taken to complete a task.</p>"}, "variablesTest": {"maxRuns": 100, "condition": "1-2"}, "tags": [], "parts": [{"showFeedbackIcon": false, "type": "1_n_2", "prompt": "<p>Attach your SPSS output here.</p>", "variableReplacementStrategy": "originalfirst", "matrix": [], "minMarks": 0, "unitTests": [], 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"name": "stdiff", "templateType": "anything", "description": "<p>Standard deviation of the difference of the left and right.</p>"}, "meandiff": {"definition": "precround(mean(d),3)", "group": "Summary Statistics of the difference", "name": "meandiff", "templateType": "anything", "description": "<p>Mean of the difference between left and right.</p>"}, "t999": {"definition": "4.437", "group": "t-values", "name": "t999", "templateType": "number", "description": ""}, "r2": {"definition": "repeat(round(normalsample(mu2,sig2)),12)", "group": "Data given in question", "name": "r2", "templateType": "anything", "description": "<p>Data for the \"left hand\".</p>"}, "t99": {"definition": "3.106", "group": "t-values", "name": "t99", "templateType": "number", "description": ""}, "mu2": {"definition": "mu1+random(2..5#0.1)", "group": "Data given in question", "name": "mu2", "templateType": "anything", "description": ""}, "object": {"definition": "'Participant'", "group": "Ungrouped variables", 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