## 04 August 2015

### Statistics: Median (Definitions)

"The middle value in an ordered set of values for which there are an equal number of values." (Jennifer George-Palilonis, "A Practical Guide to Graphics Reporting", 2006)

"The center-most value in an ordered set of values. If the set quantity is even, then the average of the two center-most values." (DAMA International, "The DAMA Dictionary of Data Management", 2011)

"The median is a statistical measure of variation. It represents the middle measurement when a set of measurements are collected in ascending order: 50% of the measurements are above the median and 50% are below it." (Laura Sebastian-Coleman, "Measuring Data Quality for Ongoing Improvement ", 2012)

"The middle value in a set of ordered numbers. The median value is determined by choosing the smallest value such that at least half of the values in the set are no greater than the chosen value. If the number of values within the set is odd, the median value corresponds to a single value. If the number of values within the set is even, the median value corresponds to the sum of the two middle values divided by two." (Microsoft, "SQL Server 2012 Glossary", 2012)

"The middle value in a set of values. Half the values fall below the median, and half the values fall above the median. See also average; mode." (E C Nelson & Stephen L Nelson, "Excel Data Analysis For Dummies ", 2015)

"To find the median, list the values of the data set in numerical order and identify which value appears in the middle of the list." (Christopher Donohue et al, "Foundations of Financial Risk: An Overview of Financial Risk and Risk-based Financial Regulation, 2nd Ed", 2015)

"Middle score in a distribution." (K  N Krishnaswamy et al, "Management Research Methodology: Integration of Principles, Methods and Techniques", 2016)

### Statistics: Mean (Definitions)

"In a numerical sequence, the number that has an equal number of values before and after it. In the sequence 3, 5, 7, 9, 11, seven is the mean." (Dale Furtwengler, "Ten Minute Guide to Performance Appraisals", 2000)

"The average value of a sample of data that is typically gathered in a matrix experiment." (Clyde M Creveling, "Six Sigma for Technical Processes: An Overview for R Executives, Technical Leaders, and Engineering Managers", 2006)

"The sum of all values in a variable divided by the number of values." (Glenn J Myatt, "Making Sense of Data: A Practical Guide to Exploratory Data Analysis and Data Mining", 2006)

"The average value of a sample of data that is typically gathered in a matrix experiment." (Lynne Hambleton, "Treasure Chest of Six Sigma Growth Methods, Tools, and Best Practices", 2007)

"The sum of all values in a variable divided by the number of values." (Glenn J Myatt, "Making Sense of Data: A Practical Guide to Exploratory Data Analysis and Data Mining", 2007)

"The result of dividing the sum of all values within a set by the count of all values included." (DAMA International, "The DAMA Dictionary of Data Management", 2011)

"The mean is a statistical measure of central tendency. It is most easily understood as the mathematical average. It is calculated by summing the value of a set of measurements and dividing by the number of measurements taken." (Laura Sebastian-Coleman, "Measuring Data Quality for Ongoing Improvement", 2012)

"To find the mean add up the values in the data set and then divide by the number of values." (Christopher Donohue et al, "Foundations of Financial Risk: An Overview of Financial Risk and Risk-based Financial Regulation" 2nd Ed., 2015)

"Arithmetic averages of scores. The mean is the most commonly used measure of central tendency, but should be computed only for score data." (K  N Krishnaswamy et al, "Management Research Methodology: Integration of Principles, Methods and Techniques", 2016)

### Statistics: Moving Average (Definitions)

"A trend-following indicator that works best in a trending environment. Moving averages smooth out price action but operate with a time lag. Any number of moving averages can be employed, with different time spans, to generate buy and sell signals. When only one average is employed, a buy signal is given when the price closes above the average. When two averages are employed, a buy signal is given when the shorter average crosses above the longer average. Technicians use three types: simple, weighted, and exponentially smoothed averages." (Guido Deboeck & Teuvo Kohonen (Eds), "Visual Explorations in Finance with Self-Organizing Maps 2nd Ed.", 2000)

"For a time series, an average that is updated as new information is received. With the moving average, the manager employs the most recent observations to calculate an average, which is used as the forecast for the next period." (Jae K Shim & Joel G Siegel, "Budgeting Basics and Beyond", 2008)

[exponential moving average:] "A moving average of data that gives more weight to the more recent data in the period and less weight to the older data in the period. The formula applies weighting factors which decrease exponentially. The weighting for each older data point decreases exponentially, giving much more importance to recent observations while still not discarding older observations entirely." (SQL Server 2012 Glossary, "Microsoft", 2012)

"An average that’s calculated by using only a specified set of values, such as an average based on just the last three values." (E C Nelson & Stephen L Nelson, "Excel Data Analysis For Dummies ", 2015)

"A mathematical average of data points over a specified period of time. Moving averages are used on financial price charts to show the average price over a selected interval of time. Examples are the SMA(9), SMA(20), SMA(50), or SMA(200) referring to 9-, 20-, 50-, or 200-period simple moving averages. Other types of moving averages also exist, such as an exponential moving average (EMA) and triangular moving averages (TMA). The EMA places more emphasis on the most recent data points. The TMA places more emphasis on the center data points of the specified range, that is, 9, 20, 50, 200, and so on." (Russell A Stultz, "The Option Strategy Desk Reference", 2019)