This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Social & Preventive Medicine
[{'content': 'All are measures of dispersion around central value except- \nSelect and explain. \nA. Mode, B. Variance, C. Standard deviation, D. Standard error of mean', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Mode is a measure of central tendency not dispersion around central tendency.\n\nMeasure of dispersion (variation)\n\nThe measures of central tendency (mean, median, mode) serve to locate the center of distribution, but they do not reveal how the items are spread out on either side of the center.\nThis characteristic of a frequency distribution is commonly referred to as dispersion.\nThere are measures to obtain this dispersion, commonly known as measures of dispersion or measures of variation.\nThere are two kinds of measures of dispersion -\n\ni)\xa0\xa0Absolute measures of dispersion\n\nIndicates the amount of dispersion (variation) in terms of unit.\nFor example, when rainfall on different days are available in mm (unit of rainfall), any absolute measure of dispersion gives the variation in rainfall in mm.\nIn simple words, absolute measure of dispersion has a unit.\n\nii)\xa0\xa0\xa0 Relative measures of dispersion\n\nIn contrast to absolute measures, relative measures are free from the units.\nThey are pure numbers.\nThey are used to compare variation in two or more sets, which are having different units of measurements of observations.\n\nAbsolute measure\n\nRange\nQuartile deviation\nMean deviation\nStandard deviation\n\nRelative measure\n\nCo-efficient of range\nCo-efficient of quartile deviation\nCo-efficient of mean deviation\nCo-efficient of variation\n\nMeasures of dispersion used\n\nTo compare variation in two or more sets, which have same units\xa0→ Absolute measures.\nTo compare variation in two or more sets, which have different units → relative measures.', 'role': 'assistant'}]