What is a population, what is a sample, the calculation formulas of sample size, frequency, variance, range and standard deviation, and the basic concepts of conceptual mathematics.
The population is the whole of your research object, the sample is the research object you extract from the population, and the sample size is the size and range of your sample. For example, a class (all) selects four people (samples) to take part in the physical examination. The sample size is four, and the frequency and probability are similar. The frequency changes and the probability remains unchanged. Variance = frequency (expected -kesi) 2+… Note that frequency is when kesi takes a certain value.