In the amortized analysis, the time needed to perform a set of operations is the average of all operations performed. Amortized analysis considers as a long sequence of operations rather than just one and then gives a worst-case estimate. There are three different methods by which the amortized cost can be calculated and can be differentiated from the actual cost. The three methods are following:

Aggregate analysis: It determines the average cost of each operation. i.e., T(n)/n.

The amortized cost is similar for all operations.
Accounting method: The amortized cost is distinct for all operations & charges a credit as prepaid credit on some of the operations.

Potential method: It also has distinct amortized cost for each of operation and charges a credit as the potential energy to other operations.

There are special operations like stack operations (push, pop, multipop) and an increment that can be considered as instance to verify the above three methods.

Every operation over a splay tree and all splay tree operations take O(log n) amortized time.