SWIN BUR . NE . STA10003 FOUNDATIONS OF STATISTICS SWINBURNE UNIVERSITY OF TECHNOLOGY Week 2 Lecture Part 1/2 Jascha Zimmermann jzimmermann@swin.edu.au KNOW ING 1 STA10003 Week 2 Part 1: Week 1 Revision & Frequency Distributions KNOW ING 2 1
3 Overview Revision of Week 1 Frequency Distributions Tables / Graphs / Percentiles / Boxplots ... PAUSE - Part 2/2 Measures of Central Tendency Mean / Median / Mode ... Output from SPSS Descriptive Statistics and Graphs Which Analysis? / Which Procedure? Revision of Week 1 Terminology: KNOW ING 3 Population: . All of the 'things' we are interested in · Can be people, households, car manufacturers, trains ... · Difficult to measure the entire population Sample: · A subset of the population · Must be representative of the population if we want to infer our finding to the general population of 'things' [population of interest] 4 Variable: · Overarching label of the element / feature we want to measure - Gender / Ethnicity / Age ... KNOW ING 4 2
Revision of Week 1 Thinking critically about statistics: Bias: [selection / information bias] · Need to AVOID bias - otherwise our findings cannot be inferred to the population To avoid bias - think critically about: · How was our sample selected? » Use random sampling where possible · How were our questions asked? » Avoid emotional language / leading questions · Who sponsored / conducted the study? » Is the source reliable / credible? KNOW ING 5 5 Revision of Week 1 Thinking critically about statistics: 3. Do you use public transport to get to Swinburne? 2. No 4. How much do you spend on Take-Away Food each week? [whole dollars only] $ 1. Yes KNOW ING 6 6 3