Of course, part of the power of histograms is that they allow us to analyze extremely large datasets by reducing them to a single graph that can show primary, secondary and tertiary peaks in data as well as give a visual representation of the statistical significance of those peaks. Note that the median is 25 and that there is no mode the mean is 26.5. The Shodor histogram activity allows you to change the bin size for a data set and the impact on the curve. Note: Changing the size of the bin changes the apprearance of the graph and the conclusions you may draw from it. In this case, with a bin width of 10, we can easily group the data as below. Instead we bin the data into convenient ranges. A graph which shows how many ones, how many twos, how many threes, etc. We graph groups of numbers according to how often they appear. Histogram Problems - These are practice problems (with solutions) so that you can construct and analyze histograms on your own.Histograms: Construction, Analysis and UnderstandingĬonservation Laws - Data Analysis Using Graphs - Histograms - Units or Vectors in Particle PhysicsĪ histogram is "a representation of a frequency distribution by means of rectangles whose widths represent class intervals and whose areas are proportional to the corresponding frequencies.".This tutorial walks you through the process of making a histogram in MS Excel. Excel Help - To work with large datasets, it helps to use a spreadsheet.Shodor Histogram Page - This is a nice interactive histogram page in which you can choose different sample histograms and vary the bin size.Sample Histogram - This is another example of how a histogram is made, with a focus on the effect of bin size.In particle physics, this could show two separate particles or, as is often the case, a large signal with "background" particles and a smaller signal (sometimes very small), called a "bump," which shows the actual particle under study. This could indicate either very poor definition of one signal in the data or, more likely, two signals. There are two peaks in this plot: a taller primary peak as well as a shorter secondary peak. Where are the median and the mean? It is hard to tell it also may not be relevant. As a particle physics mass plot, this gives an imprecise and undertain mass of a particle. There are almost as many values close to the peak as at the peak itself and outlyers are frequent. It is harder to tell from the plot what the exact location of the peak is. In this plot the peak is still fairly close to the median and the mean but it is much less defined. If this were a mass plot in particle physics, we'd say the mass is understood with good precision. Thus it can be said that deviations in this data group from the mean are of low frequency. While there are "outlyers," they are of relatively low frequency. This plot represents data with a well-defined peak that is close in value to the median and the mean. To get an idea, look at these three histograms: Histograms: Construction, Analysis and UnderstandingĬonservation Laws - Data Analysis Using Graphs - Histograms - Units or Vectors in Particle PhysicsĪ histogram is "a representation of a frequency distribution by means of rectangles whose widths represent class intervals and whose areas are proportional to the corresponding frequencies."