Conducting psychological research generally involves collecting a large amount of data. In order to summarize and draw conclusions about the data, we must first have some knowledge about the various statistical concepts. Descriptive statistics and inferential statistics are what we use to describe or summarize the data and make conclusions and predictions about a population. How variables are defined and measured is critically important in order to evaluate the validity of the research.

Why is it important for us to understand and think through how to measure different variables?

Researchers can obtain quality psychological study ndings by collecting and analyzing huge amounts of data. Psychological research is an inquiry that psychologists conduct when systematically exploring and evaluating groups or individual behaviors and experiences (Guest & Martin, 2021). However, psychological researchers rely on inferential and descriptive statistics to summarize or describe the available data and make predictions and conclusions regarding the studied population (Cameron & Stimson, 2019). Understanding the use of interval, ratio, ordinal, and nominal in measuring and dening variables is crucial for enhancing the quality of psychological research ndings. Ordinal and nominal measurement scales contain essential properties that guide the researchers in conducting the psychological study. The nominal scale is applicable in labeling the variables in various classications and does not indicate the quantitative order or value. This measurement does not contain numerical value because it enables participants to give specic answers relating to the research topic (Allanson & Notar, 2020). For example, the nominal scale help to collect data about where various people live by requesting participants indicate whether they reside in rural or urban areas. The ordinal scale measures information that is difcult to quantify. This method portrays the variables' order and does not indicate the distinction between every variable. The ordinal approach determines customer satisfaction regarding the received services by allowing them to tick different options on the provided question (Dalati, 2018). For example, different scales will show the perception of the client regarding their contentment as 1- much satised, 2- neutral, and 3- unsatised. Indeed, the ordinal and nominal scales will be vital for gathering non-numerical information about participants' viewpoints. Moreover, psychological researchers use interval and ratio scales to analyze the study variables. The interval method is a numerical scale applicable where the researchers know the order and differences between the variables. According to Allanson and Notar (2020), the interval scale can determine American citizens' income levels. For example, the interval scale will facilitate the identication of the number of U.S. residents with weekly earnings of between $1000 and $1500. Besides, the ratio scale shows the order and differences between the well-known variables and data regarding actual zero value (Allanson & Notar, 2020). For example, the ratio approach boosts the analysis of information about the weights of a group of participants by arranging their data in four categories, such as people having less than 25 kilograms, 26 to 50 kilograms, 51 to 75 kilograms, 76 to 100 kilograms, and above 100 kilograms. The ratio scale is the most challenging measure despite enhancing the accuracy and quality of study ndings (Dalati, 2018). People using this scale must recognize data's true zero, intervals, and ranks, thus, following many procedures when conducting research (Allanson& Notar, 2020). Psychological researchers must familiarize themselves with measurement scales to be effective in their research studies