How to draw Error Bars/Standard Deviation bars on a graph?
The standard deviation is huge. Make sure you have this correct and it isn’t the variance. For your question, check the first image on the following page; it may be clearer to represent each data point on the graph to give a clear idea of how much your data is actually dispersed, otherwise you may be left with three lines on a scale, looking rather insignificant. If it must be a bar chart of some sort, although I know of no standard for error or standard deviation, I would recommend a box plot. Use the “whiskers” to represent the highest and lowest data values and a cross or circle for your standard deviation. If you don’t have the highest and lowest values, use the “whiskers” for standard deviation. See the link below on how to construct a box-and-whisker plot.
