Bootstrap comes in handy when there is no analytical form or normal theory to help estimate the distribution of the statistics of interest, since bootstrap method can apply to most random quantities, e.g., the ratio of variance and mean.
Everyone has the right to change their name. Typically, you may legally change your name to whatever name you'd like. There are some exceptions, though: You can't change your name just to escape debt liability or to hide from criminal liability.
Any person can apply to change their name by Deed Poll no matter what their age is. The only thing that will be affected is whether the application is made for an adult or for a child Deed Poll.