# TODO: doc is missing

OLSbeta(y,x) = inv(x' * x) * (x' * y)

# TODO: make it a doctest string
# a = [10, 14,17,21,20, 18, 42, 51, 77, 11, 91]
# b = [0.11,0.7,0.2,0.19,0.09,0.8, 0.71,0.1, 0.6,0.3,0.81]
# OLSbeta(a,b)

# df = DataFrame(a=a, b=b)
# ols = GLM.lm(@formula(a~b), df)
# coef(ols) # print coefficients

# # Predict
# predict(ols) # predict the model