Longitudinal data is used in statistical and financial studies. Longitudinal data analysis has become popular as one of statistical methods. The process of analyzing past return data for a given security is an example of using longitudinal data. The longitudinal data are defined as the data resulting from the observations of subjects (human beings, animals, or laboratory samples, etc).
The impact factor of journal provides quantitative assessment tool for grading, evaluating, sorting and comparing journals of similar kind. It reflects the average number of citations to recent articles published in science and social science journals in a particular year or period, and is frequently used as a proxy for the relative importance of a journal within its field. It is first devised by Eugene Garfield, the founder of the Institute for Scientific Information. The impact factor of a journal is evaluated by dividing the number of current year citations to the source items published in that journal during the previous two years.
Last date updated on September, 2014