STA 2023 Lecture Notes - Lecture 9: Round-Off Error, Weighted Arithmetic Mean, Central Tendency
Document Summary
A statistic is a characteristic or measure obtained by using the data values from a sample. A parameter is a characteristic or measure obtained by using all the data values for a specific population. The basic rounding rule is that rounding should not be done until the final answer is calculated. Use of parentheses on calculators or use of spreadsheets helps to avoid early rounding error. The mean is the sum of the data values divided by the number of data values. The symbol x is used for sample mean. For a population, the greek letter mu, us used for the mean. Every set of interval-level and ratio-level data has a mean. All the values are included in computing the mean. A set of data has a unique mean. The mean is affected by unusually large or small data values.
