S 519 Evaluation of Information Systems Social Statistics

S 519: Evaluation of Information Systems Social Statistics Ch 1: Introduction

Social Statistics describes a set of tools and techniques for describing, organizing and interpreting information or data. l Do we need statistics? When and Why?

Descriptive statistics l Used to organize and describe the characteristics of a collection of data

Descriptive statistics Name Gender Major Age Score Sara Female LIS 27 A Richard Male Psychology 30 C Andrea Male Education 33 B Emily Female Language 25 B Bill Male LIS 28 C Leo Female Psychology 26 A Liz Female LIS 26 B Alice Female LIS 28 C Steven Male Psychology 24 C Jeff Male LIS 30 B How can you describe this table?

Inferential statistics l Make inferences from a smaller group of data to a possible larger one l Sample: a smaller group of data Population: the whole group of a certain subject l What can you infer from above table? l

Lab Excel and Add-in l l Excel 2003, 97 Analysis Tool. Pak l l l Tools menu, click add-ins In add-ins box, select the checkbox of analysis toolpak, click ok Install it Then you are done! You see „data analysis“ under Data menu

Why learn statistics l l l Always good to put some lines in your vita It is an important way of analysing data You need this for your evaluation

Lab Formula Operator Symbol Example What it does Addition + =2+5 Adds 2 and 5 Subtraction - =5 -3 Subtracts 3 from 5 Division / =10/5 Divides 10 by 5 Multiplication * =2*5 Multiplies 2 times 5 Power of ^ =4^2 4 power of 2 How does it work in Excel?

Lab Function l Sum() l l =sum(3, 4) =sum(a 2: a 4, 6) =sum(a 6: a 8, 4)

Lab Example l Students in 3 evaluations