[educationdata]

I actually think you are more possibly to make mistakes in R than in Excel. Because in Excel you always see the results directly, and you can even easily catch an anomaly in a single cell. But in R it takes one more step to see the results, and you probably won't see results of all the rows directly.

[_Wintermute]

Especially when R really likes to carry on chugging along with your analysis spitting out nonsense values when it should have failed on something 50 lines ago.

    sum(1, 2, 3, 10)
    [1] 16 # great

    mean(1, 2, 3, 10)
    [1] 1 # wait, what?