We study a formulation of statistical mechanics in the context of symplectic structures of the IR and also UV & IR-deformed Snyder phase-spaces. We derive the corresponding invariant Liouville volume and by using it we obtain the deformed partition function. We then study the thermodynamical properties of the 3-dimensional harmonic oscillator in this set-up. By using the equipartition theorem, we show that two of the six degrees of freedom for a 3-dimensional harmonic oscillator will be frozen as the temperature increases. Also, at a constant temperature, whatever is the increase in oscillator length, this reduction of the number of degrees of freedom gets more and more appreciable and it offers an effective dimensional reduction of space from 3 to 2 when it is close to the IR-length scale.
