Sampling Methods. In the research process, once the researcher decides who to study, they then need to select a sample from a target population. To do this, the researcher selects from two basic sampling methods: probability and non-probability.In probability sampling, each element of the population has a known chance of being selected.o do this, the researcher selects from two basic sampling methods: probability and non-probability. In probability sampling, each element of the population has a known chance of being selected.
DOI: 10.1631/jzus.C1010311. Baseline wander is a common noise in electrocardiogram (ECG) results. To effectively correct the baseline and to preserve more underlying components of an ECG signal, we propose a simple and novel filtering method based on a statistical weighted moving average filter. Supposed a and b are the minimum and maximum of all sample values within a moving window, respectively.
An EKG is done to: 1  Check the heart's electrical activity. 2  Find the cause of unexplained chest pain or pressure. 3  This could be caused by a heart attack, inflammation of the sac surrounding the heart (pericarditis), or angina. 4  Find the cause of symptoms of heart disease. A stress EKG is a type of EKG done during exercise. 2  A resting EKG is always done before an exercise EKG test. 3  Results of the resting EKG are compared to the results of the exercise EKG. 4  A resting EKG may also show a heart problem that would make an exercise EKG unsafe.