View Discussion Improve Article Save Article Like Article View Discussion Improve Article Save Article Like Article In simple words, statistics implies the process of gathering, sorting, examine, interpret and then present the data in an understandable manner so as to enable one to form an opinion of it and take necessary action, if necessary. Examples:
Statistical Tools The most popular tools of statistics are as follows:
Grouped DataSuch data as is expressed in the form of class intervals and not as an individual unit is termed as grouped data. As the name suggests, the observations are grouped together to form intervals, which then are assigned frequencies pertaining to the number of times all the units belonging to that particular interval appear in the given data set. Such intervals make it very easy to analyze the data set on hand and help interpret and communicate effectively and quickly. Example:
This method of grouping data makes it so much easier to calculate the measures of central tendency, especially when the data set is large, like in the above case. It would be a tedious process to write down the marks scored by all 60 students, arranging them in ascending order to calculate median, or list them out, add them up and divide it all by 60 to calculate the arithmetic mean. In other words, grouping makes the data set shrink a bit so that the calculation process can be simplified, and results are calculated effectively since there is a chance of error in the case of handling such a large ungrouped data set. Arithmetic Mean for Grouped DataThe following steps are required in order to calculate the arithmetic mean for grouped data:
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Sample QuestionsQuestion 1. Calculate the arithmetic mean for the following data set using direct method:
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Question 2. Calculate the arithmetic mean for the following data set using the direct method:
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Question 3. Calculate the arithmetic mean for the following data set using the direct method:
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Question 4. Calculate the arithmetic mean for the following data set using the direct method:
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