Raspberries are high-valuable soft fruit for growers. But it is even more interesting for them to grow during wintertime when weather as in Portugal is still favorable, as the offer is low on the market and they can distinguish really easily and sell raspberries at high prices. ‘Sapphire’ is currently …

Potato, came from south America long time ago, the tuber is grow about everywhere in the world to become the fourth worldwide crop. Its worst enemy is an oomycete, the Phytophtora infestans. This disease is responsible for millions of deaths and forced migration in Ireland during the Great Famine from …

The assumptions of the model for factor analysis do not exclude a class of indeterminate covariances between factors and error variables (Grayson, 2003). The construction of all factors of the model for factor analysis is generalized to incorporate indeterminate factor-error covariances. A necessary …

The subject of factor indeterminacy has a vast history in factor analysis (Guttman, 1955; Lederman, 1938; Wilson, 1928). It has lead to strong differences in opinion (Steiger, 1979). The current paper gives necessary and sufficient conditions for observability of factors in terms of the parameter matrices …