Representative samples are an important tool for assessing changes in society. They can be used to study various aspects of life, such as politics, religion, economics, culture, education and many others. Representative samples are essential for creating reliable conclusions and drawing inferences about society. To calculate representative samples, it is necessary to consider the entire population from which the data is drawn. Representative samples are calculated according to the smallest possible statistical error, which states that samples must be large enough for the result to be reliable. To select a reliable sample, it is necessary to take into account all measures that are valid for the entire population.
As for examples of nationally representative samples, one of the most important is the CSO survey, which is done annually to determine the nature of the population. This sample is created by randomly selecting about 10,000 households from across the country. Survey participants are asked about issues such as ethnicity, education, employment status, income level and many others. As for examples of representative samples for selected cities, one can mention a survey conducted in 2017 in Krakow. It was conducted using a random sampling method, and the goal was to determine the nature of the city’s society. Survey participants were asked about their family, political, social, religious and economic lives.
Another example is a survey conducted in Warsaw in 2019. There, 1,000 questionnaires were sent to randomly selected households from across the city. The survey included questions about, among other things, employment status, education level, age of household members, income and many other factors. The conclusion is that representative samples are an important tool for creating reliable conclusions about society. These samples are calculated in accordance with the law of central limitation, which states that the sample must be large enough for the results to be reliable. Examples of representative samples for the whole country and selected cities are listed above.