STATISTICAL METHODS

In studying the statistics, we are basically concerned with the presentation and interpretation of the events that are opportunities that occur in a planned investigation or scientific research. For example, we recorded the number of times per month the junction Jewel accident and Manggarai, reasons need to get a traffic light installed, or we record the response of "yes" or "no" in an opinion poll, and others.

So, statisticians usually work with numeric data in the form of chopped or results or measurement results with categorical data that may be classified according to certain criteria. We will refer to any recorded information, whether it is numeric or categorical as observations.

Statistical methods are the procedures used in the collection, presentation, analysis and interpretation of data. We will classify these methods into two major groups, namely descriptive statistics and inferential statistics.

• Descriptive Statistics are methods relating to the collection and presentation of a range of data so as to provide useful information. Ought to be understood that the descriptive statistics provide information only about the data that belongs to and did not draw any inference or conclusion about the data clusters larger parent.
• inferential statistics are all statistical methods associated with the analysis of some data for forecasting or later arrive at a conclusion regarding the whole range of data parent. Yag generalizations related to statistical inference has always uncertain nature, because we are basing on partial information obtained from partial data.