This paper defines and explains, in simple and clear terms, key concepts of descriptive statistics and connects statistical theory with applied statistical practice through real cases. It begins by clarifying the meaning of statistics and the basic notions used daily in many fields, while distinguishing statistics as a science and an art from statistics understood as data and measures. The study adopts the following definition: “Statistics is simply an art and a science that allows for the collection, analysis, presentation, and interpretation of data for the purpose of making decisions about any phenomenon under study.” To illustrate these concepts, practical applications were carried out using real data from two institutions: AL BANK and a non-governmental organization. For the calculations and applications, EXCEL, EVIEWS, and R STUDIO were used. In the AL BANK case, relative frequencies were calculated step by step with the three software programs and then verified manually using the mathematical frequency formula. In Excel, the process involved entering the data, computing the total number of observations, and calculating the relative frequencies. In EVIEWS, the observations were entered, descriptive statistical measures including the total were obtained, and relative frequencies were then calculated. In R STUDIO, the data were entered as a vector and relative frequencies were computed. The three methods produced identical results, showing that 66% of AL BANK employees are single, 31% are married, 2% are widowed, and 1% is divorced. In the non-governmental organization case, the variable “business opening” was used to calculate cumulative frequencies. The procedure consisted of constructing the absolute frequency table, the relative frequency table, and then the cumulative absolute and cumulative relative frequency tables. The analysis showed that, in terms of cumulative absolute frequency, ten individuals reported that they sometimes or often open their businesses. Regarding relative frequencies, six out of sixteen individuals reported often opening their businesses (37.5%), while 25% sometimes open their businesses, 25% rarely open them, and 12.5% never open them. These findings highlight the importance of frequency as the one of the fundamental concepts of applied statistics.
Alain Yamwembo (Thu,) studied this question.