Calculating standard deviation by hand can be laborious. \u00a0Keeping track of what you’ve entered, making sure the brackets have been put in right…most people (including myself) will unlikely enter everything correctly the first time. \u00a0In a future post, I’ll show a way to organize the procedure so you do<\/em> succeed. \u00a0Today, though, I have some better news: \u00a0maybe you don’t have to.<\/p>\n I’ve never met a scientific calculator without a standard deviation function. \u00a0Today, for instance, we have the Sharp EL-520W. \u00a0I don’t own any other Sharp calculators, but I imagine this process will be similar for most Sharps worth between $8 and $25.<\/p>\n Example: \u00a0Find the standard deviation of the following list: \u00a0{-18,16,0,45,100,32,27}<\/strong><\/p>\n Solution:<\/strong> With the Sharp EL-520W, you need to go into STAT mode to access the statistical functions.<\/p>\n Press MODE<\/span>. You’ll see a choice of NORMAL or STAT. Press 1<\/span> for STAT mode. You arrive at another list of choices: SD, LINE, or QUAD. Press 0<\/span> for SD. You should now be back at the calculation screen, with STAT 0 showing at top left.<\/p>\n We are ready to enter our numbers, as follows:<\/p>\n Type in -18, then the DATA<\/span> key. Note: the key’s main label is M+<\/span>; however, if you look at the printing below it, you’ll see the DATA label in white.<\/p>\n You’ll know if it’s working: after you press the data key, you should see DATA SET= across the top. Right now, a 1 should appear, since -18 is your first number.<\/p>\n Next, type in 16, then press the DATA<\/span> key. You should now see DATA SET= with a 2. The 2 means, of course, that 16 is your second number.<\/p>\n Continue: enter each number, then DATA<\/span>. After keying in 27, then DATA<\/span>, you should see DATA SET= with 7. Having entered all seven values in the data set, you are ready to find the standard deviation.<\/p>\n Look at the 6<\/span> key. The\u00a0\u03c3x<\/sub><\/span> label appears in green just above it to the right. Because\u00a0\u03c3x<\/sub><\/span> appears in green, we need to press the green ALPHA<\/span> key to access the\u00a0\u03c3x<\/sub><\/span> function.<\/p>\n Press ALPHA<\/span> 6<\/span> =<\/span>. You should get the result 34.9.<\/p>\n A few points:<\/p>\n 1) You will notice that the 5<\/span> key has a green sx<\/sub><\/span> label above it to the right. sx<\/sub> means\u00a0\u03c3n-1<\/sub>. If your statistics course prefers\u00a0\u03c3n-1<\/sub>, use ALPHA<\/span> 5<\/span>instead of ALPHA<\/span> 6<\/span>.<\/p>\n 2) Before entering a new data set, you should clear the memory, so that no old data affects your new results. Therefore, press 2nd F<\/span> MODE<\/span> to “Clear All.”<\/p>\n 3) When you’re done with statistical calculations, you might want to return to the mode you were at previously. Most likely, it was normal mode. Press MODE<\/span> 0<\/span> to get back.<\/p>\n In upcoming posts, I’ll outline the standard deviation procedure for other scientific calculators.<\/p>\n