Descriptive and Inferential Statistics free essay sample

Running head: DESCRIPTIVE AND INFERENTIAL STATISTICS 1 Descriptive and Inferential Statistics DESCRIPTIVE AND INFERENTIAL STATISTICS 2 Descriptive and Inferential Statistics Descriptive and inferential statistics are incredibly similar forms of research testing within psychology. Each seeks to analyze, describe, and possibly predict a population’s behavior. As with psychology itself, statistical analysis within psychology began as a philosophy (Goodwin, 2008). This philosophy quickly turned to a scientific pursuit, again mirroring psychology itself. A person observes, and wonders why that event occurred. That person makes a guess, known as forming a hypothesis, then he or she observes the situation again making small changes to test the theory. Once the determination that the behavior or occurrence is prevalent in a population for which the statistical study is relevant it is given a level of probability (A. Aron, E. Aron, Coups, 2009). Statistics has two branches descriptive and inferential, and both branches use fundamental concepts as measurements of predictability. We will write a custom essay sample on Descriptive and Inferential Statistics or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page The predictability or probability of an event or behavior is determined through values, variables, and scores. Statistics would be redundant if data given by considerable surveys’ and testing were simple to interpret. However, the mass of information concerning a sample of a parameter used in inferential statistics, and a parameter used in descriptive statistics has become the easiest known way to interpret data (University of California, 1998). Expressed differently, raw data are difficult to visualize and translate into descriptive or inferential statistics (Leard Statistics, 2010). Properly interpreting data and graphing it in an easily understandable truthful manner is the major function in descriptive and inferential statistics. Descriptive Statistics Descriptive statistics summarize numbers in a set of data, such as mean or median, and values, or scores (A. Aron, E. Aron, Coups, 2009). Descriptive statistics are used when data DESCRIPTIVE AND INFERENTIAL STATISTICS 3 are to be analyzed in a small sample of research, which will not include the entire population. As the name implies, statistics give psychologists the ability to understand easily the collection of numbers they are researching. This is made possible because histograms, frequency tables, charts, and pictures enhance the data provided. To display numbers in a visually appealing manner, research becomes easier, and there is less room for error. Descriptive statistics focus on the research of a small section of the population provides information about the sample population. Inferential statistics; however broadens the use of these samples, to make inferences about the entire population. Inferential statistics and descriptive statics go hand in hand. Without descriptive statistics, researchers would not have small samples of population to make inferences about the entire population. Inferential statistics use methods such as random selection and probability to determine data needed for research (A. Aron, E. Aron, Coups, 2009). These two branches of statistics could work well together if an entire state was debating on whether or not to allow gay marriage. Using this as an example, descriptive statistics would target one specific area of the state, possibly as small as half a city. The researchers would survey the population in this area, and collect the descriptive data from around the state to infer what the entire state thought about gay marriage. The researchers would have a ton of descriptive data, which they could randomly select from, and based on probability they could produce a statistic about the state’s thoughts. Inferential Statistics Inferential statistics are sample scores that researchers collect during a research study. The scores (data) collected allow the researcher to establish conclusions and make inferences about the research study. The inferences made on the research study are obtained by using a relatively small group of participants. Although only a small group of participants are in the DESCRIPTIVE AND INFERENTIAL STATISTICS 4 study, the outcome of the research study makes inferences about a much larger group of people (A. Aron, E. Aron, Coups, 2009). Additionally, when using inferential statistics the inferences about the research study exceeds the numbers collected in the study (A. Aron, E. Aron, Coups, 2009). Therefore, the inferences communicate exactly how reliable data collected for the research study is. The inferences in inferential statistics also convey how significant the information collected is. The information researchers gather for their study only shows a sampling of the group of participants that the researchers use. This sampling used must vary enough to be representative of the reliability and significance of the research study (â€Å"Research Methods,† n. d. ). There also must not be much variation in the data (scores) obtained for the study. When using inferential statistics the researcher must prove that the results of the study are not based on chance or the outcome leads to chance (â€Å"Research Methods,† n. d. ). Ideally, if the result is a probability, the researcher’s observation of the difference would be statistically significant (â€Å"Research Methods,† n. d. ). The difference would be the difference in the variables used in the study. Researchers must use descriptive statistics to establish a research study that is statistically significant. The use of descriptive statistics provides the researchers with a summary and organization of data used (â€Å"Research Methods,† n. d. ). The researchers use histograms to make a visual representation of the use of data in the study (â€Å"Research Methods,† n. d. ). Therefore, it is palpable that the use of inferential statistics is another measure of analyzing and interpreting numerical data collected in a research study. DESCRIPTIVE AND INFERENTIAL STATISTICS 5 Conclusion Statistics are an important part of almost every field of research study, which includes medicine, psychology, physics, and many others. The only way to gain information and knowledge about scientific outcomes is to study and observe them. When we achieve results from a research study, we are using statistics. Researchers use two types of statistics descriptive statistics and inferential statistics. Both types of statistics help researchers to comprehend data that they have collected. Statistics are important and are in use every day without people even knowing that they are using it. Research is extremely important to understanding the world we live in, and after compiling the research data collected, we can put our data into a statistic form for everyone to understand. DESCRIPTIVE AND INFERENTIAL STATISTICS 6 References Aron, A. , Aron, E. N. , Coups, E. (2009). Statistics for psychology (5th ed. ) Upper Saddle River, NJ: Pearson/Prentice Hall California State University. 1998). Definition of Descriptive and Inferential Statistics Retrieved from http://www. scudh. edu/dearhabermas/stat2f98. htm Goodwin, C. J. (2008). A history of modern psychology (3rd ed. ). Hoboken, NJ: Wiley Leard Statistics. (2010). Descriptive and Inferential Statistics. Retrieved from http://statistics. laerd. com/statistical-guides/descriptive-inferential-statistics. php Research Methods in Psychology. (n. d. ). Retrieved August 8, 2011, from http://www. sparknotes. com/psychology/psych101/researchmethods/section5. rhtml