may i know what is the usage of Missing Values Dialog Box in SPSS 13.0?
how to define missing values?
hope someone can help.
thank you.

A "missing value" in SPSS represents a known datapoint with an unknown value. In other words, if you had an SPSS dataset with hourly temperature data, but the probe was inoperable for a four hour span one day, you'd still want the data points (one for each hour), but the temperature value would be missing. This can be crucially important for proper statistical distribution.

-PatP

thanks about that.
what about the dialog box that prompt us about the discrete missing values?

http://img32.exs.cx/img32/8864/spss2ol.jpg

what are the 3 values represent there?
thanks a lot