When conducting a study, we normally collect relevant data for it. These data may be different in types and nature. Each type of data has its own merits and demerits. Therefore, we adopt separate statistical approach or method for analyzing and interpreting each distinct type of data, because we can’t efficiently handle each and every type of data with the same statistical approach or method. But if we do so, either intentionally or unintentionally, then our study may give us invalid results. Therefore, it should be kept in mind that types of data play an important role in shaping all our research activities. Normally we categorize data into four distinct levels or classes. These classes or levels of data are called scales of measurement. They are: nominal, ordinal, interval and ratio.
