HP provides a type of model name near the keyboard or screen, but this name or number is probably not sufficient to get proper support for your computer. These names or numbers often represent a series of many notebook computers that look similar, but have different options and parts.
Fundamentally, river sampling is a web-based convenience sample of opt-in participants that uses a quota sampling approach to build a study sample. The selection method is not probability based, and participants cannot be described as representing any larger defined population.
Cluster sampling is considered less precise than other methods of sampling. However, it may save costs on obtaining a sample. Cluster sampling is a two-step sampling procedure. It may be used when completing a list of the entire population is difficult. For example, it could be difficult to construct the entire population of the customers of a grocery store to interview.