RWORD – TECHNICAL BLOG

Have you ever had a professor or a boss give you an assignment that could not be done in a reasonable amount of time? Wouldn’t it be great to be able to say that you have some statistical proof that it would take an unreasonable amount of time? Well I developed a quick and dirty method to calculate how long a task will probably take based on past experience. All you need to know is a little simple math and have access to a spreadsheet program such as Google-Documents.
First, pick the task that you want to track. How you do this is up to you. Do you want to measure how long it takes you to read a chapter, read a page, finish a whole book, or do one homework assignment? It’s up to you. Be aware that a highly related task will be the easiest to predict (don’t put reading a children’s book and reading a Milton book in the same category). I am picking the amount of time it takes me to read a Modern Global History chapter. My first four chapters took 1.1, 1.5, 1.75, 1.25 hours to read, respectively.

So enter these numbers in Google documents (Excel or even a calculator would work fine too). Also, add the labels for mean, standard deviation, and our prediction min and max.

Next we will calculate the mean and standard deviation for these numbers. Click on the cell beside “Mean” and type “=AVERAGE(A:A)” and press enter. You can find functions like this by clicking on the “Formulas” tab and selecting more (there are quite a few things to choose from). By putting “A:A” in the AVERAGE function we can add as many numbers as we want to the column A and it will compute a new average. Click on the cell next to Standard Deviation and type “STDEV(A:A)” and press enter.
Now we can computer our min (average – standard deviation) and max (average + standard deviation). Since we have the appropriate cell selected, type “=” then click on the mean (in this case 1.4), type “-” and click on the standard deviation (in this case 0.2857…) and press enter. Repeat the same for the max but use a “+” instead. This is what we get:

So in conclusion, for this example, I can expect to spend between 1.1 and 1.7 hours on reading a chapter for my Modern Global History class. Of course, the more data you have, the more accurate you can predict.

Hello all!
Now that I have come to realization technical blogs are good, I have made one! I will soon have some work that I have done, am doing, and have yet to do. Enjoy the soon to come spectrum of goodness! In the mean time, have a look at my current project for statistical quality assurance. My professor did not ask for it, but I was inspired by my Software-Engineering professor to make an SRS for it.