y1 = [49.20 44.54 45.80 95.84 30.10 36.50 82.30 87.85 105.00 95.22 97.50 105.00 58.05 86.60 58.35 72.80  116.70 45.15 70.35 77.40]'
y2 = [97.07 73.40 68.50 91.85 106.60 0.57 0.79 0.77 0.81]'
y3 = [62.10 94.95 142.50 53.00 175.00 79.50 29.50 78.40 127.50]'
y4 = [110.60 57.10 117.60 77.71 150.00 82.90 115.50 101.63]'

n = [length(y1), length(y2), length(y3) length(y4)]

b4 = [
