University of Zagreb. Faculty of Science. Department of Mathematics.
Abstract
U ovom radu, uveli smo osnovni faktorski model te predstavili faktorske modele glavnih komponenti i faktorske modele maksimalne vjerodostojnosti. Vidjeli smo da je polazna točka faktorske analiza kovarijacijska (korelacijska) matrica podataka. Određivanje faktorskog modela se svodi na određivanje matrice koeficijenata te zajedničkih faktora. Uočili smo da se modeli međusobno razlikuju po dodatnim pretpostavkama i načinu određivanja matrice koeficijenata. Nakon predstavljanja modela, obradili smo testove za testiranje da li postoje zajednički faktori te koliko ih ima. Za to se koristi χ2 test te Akaikeov (AIC) i Schwarzov (SIC) informacijski kriterij. Spomenuto smo potkrijepili primjerom. Nakon toga smo opisali procjenu faktora. Ona se razlikuje s obzirom da li na faktore gledamo kao na slučajne varijable ili fiksne parametre. Na kraju smo dali primjer u kojem smo sproveli faktorsku analizu.In this work, we have introduced the general factor model and presented principal components factor models and maximum likelihood factor models. We have seen that the starting point of the factor analysis is the data covariance (correlation) matrix. Determining the factor model comes down to determining coefficient matrix and the common factors. We have observed that there is a difference between various factor models in additional constraints and the method of determining the coefficient matrix. After presenting the models we elaborate tests for testing if common factors exist and how many common factors there are. For that purpose, we used χ2 test and Akaike (AIC) and Schwarz (SIC) information criteria. We showed mentioned in the example. After that we have described the factor estimation. It differs depending on whether we consider the factors as random variables or fixed parameters. Finally, we gave an example where we implemented a factor analysis