This chapter opens data file dist-norm.sav. Select [conversion] - calculated variables, generates a new variable dist01 in the data view. Builder graphically plotted line chart dist01 choose [conversion] - [calculated variables], create a new variable density01, select [pattern] - [Chart Builder]
Here we use the PDF of spss function calculation function value corresponding to the exact density values of x, denoted as variable ExactDens01, repeat the process, the value of the variable density function generating additional different distributions, N (1,1) is the density function "ExactDens11", N (0.3) density function value "ExactDens03"
Select [Graphics] - [Old dialog] - chart, select the "Multi-line charts," data in the chart is the case check box value option, click the Customize button,
Clicking [OK] button, a density function graph, it is found from FIG. 3 density function curve distribution, N (0.1) of the density function of a unit that is shifted to the right in FIG N (1.1) density function curve, therefore, N (0.1) and N (1.1) exactly the same pattern shape. And (0.3) is a number of flat, tails much larger than N (0.1) and N (1.1), indicating that the probability of occurrence larger value and a smaller value is relatively high.
We observed relative frequency distribution of sample data is called the empirical distribution.
Open the chapter data GSS2004.sav, select - Analysis - Frequency, click the chart to select bar in the chart, select the chart percentage value box.
Click the Continue button to return to the frequency, click the OK button,
Due to the randomness of the sample selection, sample statistics are different samples of random variables, sample statistics values may be different, consider the sample mean, it depends on n observations samples, different samples may have different observations the sample mean may be different. Select - Open - syntax selection Ssmple80.sps then select [Run] - [All], the data editor 80 generates a new variable, respectively, X1, X2, ... X80.
Save the newly generated data files Ssmple80, sav, select [analysis] - [descriptive statistics] - Description.
Click the Select button to get the option to click Continue to return descriptive dialog box, click OK, here, I mean we examine the case of the 80 variables. Then copy them to a new spss data files. Variable named means, the data file is saved as Sample-means, sav. Histogrammed normal curve with the variable means.