Stati̇sti̇cal wei̇ghted mean summabi̇li̇ty of double sequences of fuzzy numbers

This study consists of three chapters. The first chapter is introduction chapter. In this chapter historical developments of Tauberian theory and the notion of statistical convergence are mentioned. Studies concerning with statistical summability of double sequences are summarized. Also, information about fuzzy set theory are given and the aim of this thesis are introduced. In the second chapter, first, Tauberian conditions for double sequences that are statistically summable by weighted means are given. Next, the notion of statistical A-summabilitiy for double sequence is defined. Finally, basic definitions and theorems related to fuzzy numbers and fuzzy positive linear operators are given. In the third chapter, original results of this thesis are given. In this chapter we definethemethodofstatisticalsummabilityofweightedmeansoffuzzydoublesequences and we give Tauberian conditions under which statistical convergence of fuzzy double sequences follows from the statistical summability of their weighted means. Furthermore by means of our new method We prove a Korovkin-type approximation theorem for a double sequence of fuzzy positive linear operators.