Descriptive and Inferential Statistics2

Descriptive and Inferential Statistics The world of science would find itself lost without research. Research alone however, oftentimes will not answer the questions or solve the problems that scientists set out to solve. Statistics is where research becomes applied and scientists can make educated guesses about future outcomes. â€Å"Formally, statistics is a branch of mathematics that focuses on organization, analysis, and interpretation of a group of numbers† (Aron, Aron, and Coups, 2006). There are two main branches of statistics that we will explore; descriptive and inferential statistics. The main relationship between descriptive and inferential statistics is that they all include numbers from either actual given information or inferred assumptions that try to draw a conclusion or complete given data. Descriptive Statistics Descriptive statistics is a method of research used by psychologists. Descriptive statistics make statistics understandable and describes a group of numbers for a research study (Aron, Aron and Coups,2006). Descriptive statistics are used in summarizing large sets of quantitative or numerical information. If there is a large amount of information for measurement, the best way to show the information is by a graph (Boerre, 2005). Descriptive statistics provide a simple summary about the sample and the measurements. Descriptive statistics describes the data; it allows the researcher to understand a large amount of numbers or data in a simple way (Social Research, 2009). Central tendency refers to the idea that one number can summarize the entire set of measurement. This is a number that is in some way central to the set (Boerre, 2005). The mode is the measurement that has been found to be the most frequent. Although the mode, or greatest frequency number, is not used very often, it is useful when differences are rare or non-numerical (Boerre, 2005). The median is the number which is half of the measurement, or midpointof the numbers. The median is a good measurement of the centrality of the numbers and is a better measurement in centrality that the mean when the data is skewed (Boerre, 2005). The mean is the average. The mean is the sum of all the measurements, divided by the numbers of the measured. Mean is often used in central tendency (Boerre, 2005). Descriptive statistics may be used in measuring a person’s IQ. When intelligence testing is done, some of these tests are then shown in descriptive statistics. Descriptive statistics might also be used in showing the GPA or grade point average of a class. Descriptive statistics makes information clear, concise, and easy to read (Social Research, 2009). An example of descriptive statistics would be tables and graphs which are used a lot in medical research studies. Descriptive statistics allow a researcher to describe or summarize their data. For example, descriptive statistics for a study using human subjects might include the sample size, mean age of participants, percentage of males and females, range of scores on a study measure, descriptive statistics are often briefly presented at the beginning of the Results†, according to, (Statistically Significant Consulting, LLC, 2003-2010). Inferential Statistics Conclusio n Statistics gives form to research in that it organizes, analyzes, and interprets the data collected. Descriptive statistics often describe groups or populations researched, whereas inferential statistics help its users draw conclusions about future events. Both of these statistical methods play valuable roles in science. References Aron, A. , Aron, E. , & Coups, E. (2006). Statistics for Psychology (4th ed. ). Upper Saddle River, NJ: Pearson Prentice Hall. Statistically Significant Consulting, LLC, (2003-2010). Statistics Overview. Retrieved from http://www. statisticallysignificantconsulting. com/statistics101. htm