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145 Descriptive statistics Calculating descriptive statistics is the first step in analysing quantitative data. Descriptive statistics are used to describe general characteristics of a set of data that includes frequencies, counts, averages and percentages. Descriptive statistics simply use numerical procedures or graphical techniques to organise and describe the characteristics or factors of a given sample. The main aim of these statistics is to describe the midpoint of a spread of scores, usually referred to as the measure of central tendency, and the spread of scores known as the dispersion or variance (Fisher & Marshall, 2009). These summary descriptives accurately describe large volumes of data with a fewer values that are easier to understand. To begin with, the distribution of the data can be analysed using a frequency distribution. A frequency is simply a uni variate−a single variable that refers to the number of observations or occurrences. Methods of summarising and describing sets of numerical data can be classified as either numerical or graphical. Numerical methods summarise data in form of numbers such as percentages or means that are tabulated in a table. Graphical methods involve the presentation of data in graphical or pictorial forms like graphs. In a graphical sense, values of observations are plotted on the horizontal axis with a bar showing how many times each value occurred in the data set. This chapter shows how descriptives statistics can be obtained by the use of graphs. SPSS includes several commands specifically designed to produce descriptive statistics. This chapter looks at three commands that produce descriptives: Descriptives, Frequencies and Explore. The descriptives and frequencies commands produce a variety of useful descriptive statistics that may need further grouping. In the case of grouping, the Explore command can be used. Steps to producing the descriptive statistics using the DESCRIPTIVE command in SPSS 1. Ensure that all data has been entered into SPSS, checked, cleaned for possible errors and saved. 2. Go to Analyse on the Top of the Viewer Window. 3. Analyse will bring a dialogue box containing several commands. 4. Select Descriptive Statistics , another dialogue box containing with further commands will come 5. Select Descriptives 6. After choosing the Descriptive command, a window with two Boxes will pop up. The left box contains all the variables in the data set while the right side contains a box in which all the interest variables for descriptive analysis will be put. Placing the interest variables into the right-side is done by using the arrow ( ) that is in between the two boxes. All that is required is to click on the