Published online by Cambridge University Press: 01 January 2025
In his article “Finite Markov Processes in Psychology,”G. A. Miller derived a least-squares “estimate” for a matrix of transitional probabilities. However, the mathematical proof is found to be invalid.
On page 158, Miller defined by the equation
= N + C,
“where the elements of the matrix C are the corrections that must be added to the observed values in N to give the best estimate ”.
* Psychometrika, 1952, 17, 149-167.
† For a valid mathematical proof of a least-squares estimate in this connection, see Goodman's “A Further Note on ‘Finite Markov Processes in Psychology.’” This issue, 245-248.
† tWe note here the distinction between Miller's matrix differentiation and that of Dwyer and Macphail, Symbolic matrix derivatives. Ann. math. Statist., 1948, 19, 517-534, esp. 523, 528-530.
* We note that this argument does not apply to Goodman's results, where M, N are column vectors.