Single propagation models are investigated for analyzing VLF electromagnetic wave fields observed in magnetosphere. They are selected according to the values of the eigenvalues of the spectral matrices of the three magnetic field componenets. If there is one single nonzero eigenvalue, a one-direction model is considered, while if there are two nonzero eigenvalues, a two-direction model is chosen. A likelihood ratio test is performed in the doubtful cases. The two models are used to analyze VLF chorus and hiss observed onboard the Geos 1 satellite. The two-direction model is generally the most likely, suggesting that waves are simultaneously generated at all wave normal directions.