I am in a bit of a situation. I used this formula in excel =(STDEV(B2:U2)/SQRT(20))*SQRT(2)*0.5*2.093 long back to calculate LSD. I can think that 20 here means the sample size and 0.5 seems to be the confidence level but I can't remember what is sqrt(2) and 2.093 (is this the t critical value if yes how can I calculate it?).
What I want to do is I have two sets of data, each set has 78 rows that are categories and 20 columns with 20 observations for each category. I am plotting a line graph of these 78 rows on x-axis with the averaged values of 20 columns on y-axis . Now I wan to put LSD as y error bars. I have used the above mentioned formula long back but now can't remember the details.