king list can be used at schools where all the school-leavers will be ranked according to their grades from the highest to the lowest. The perception of ranking list can vary according to the scale. For example if there are 50 applicants for a position and they are ranked on the scale from 0 till 5, there will be no difference between applicants sharing the same rank, but if the same applicants are ranked from 0 till 50, then much more information will be takes into consideration and the difference within 5 or 10 points can be crucial.of central tendency in descriptive statistics are used to calculate the average among all the scores. Within these measures it is possible to identify further calculations. Mean is measured by dividing the sum of all possible scores into the score group of students got. Median is what can be found in the middle of score distribution, while mode is the most common amount of scores students get. If the group of students presents on the average level without a big difference of knowledge level, then the median and the mode can be equal. But if there are mane extreme points, then these data will be different. Standard deviation is the most used calculation in statistic data. There is a special formula to calculate it, but it is based on the mean score.after the data collection process a researcher can find out that some data are missing. Missing data means that a researcher planned to get special amount of data from different sources (participants, documents or other information) but either because of carelessness or some unpredictable situations the plan did not work. If the expected participants are students, it can happen that some of them do not come to school because of sickness, there is always a human unpredictadness. In this case if many participants are missing, probably it will be better to postpone the data collection process for few days. It is always better if everything works according to the plan, but if some data are missing, then the idea of ​​the whole research and later results can be useless. But even if some data are missing, the researcher must be honest and write it in the study, but never try to cheat by giving wrong information.analysis process can be always conducted on two levels: multilevel or one level grouping. For example a researcher collected data about students perception of teacher s work with seven-graders. On the one level grouping a researcher will concentrate only on these particular students and on one or several chosen teachers. But if the data are analyzed on a multilevel then the researcher has to look at the situation in a wider way and look at teacher s work on the whole school level.statistical d...
