A number of my students come to me struggling with statistics.
A very common problem is that they don't have a clear understanding of how to analyse data using a Frequency (Distribution) Table.
In this video I explain that statisticians have two fundamental questions that they ask about all data that they study: "Where do the scores mostly lie?" and "How spread out are the scores?"
The first question is seeking what statisticians call "measures of central tendency." They call these measures "averages," which is why we must be very careful in using the term "average" around a statistician! For them, it can have quite a few different meanings. What most of us call an "average" in daily life a statistician would call an "arithmetic mean" or, simply, a "mean." Of the many measures of central tendency that interest statisticians, the three most commonly studied in schools are: the (arithmetic) mean, the mode and the median.
The second question is seeking "measures of spread." The three measures most commonly studies in schools are the range, Inter-Quartile Range and Standard Deviation.
In using a table to analyse data, each column has a job to do. I explain how the first column (the 'Score' column) is used to find the Range; the second column (the 'Frequency' column) is used to find the Mode; the third column (the 'fx' column) is used to calculate the mean; and the fourth column (the 'cf' column) is used to find the median score.
You will also learn what some of the symbols mean (Σf, Σfx, σ, and x̄). You will even learn of a women's fashion magazine called MODE that is no longer published but has great relevance for understanding statistics.