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# Comparing Variables

 9 Compare multiple variables Comparing Series (Auckland Uni) (Excellence) Investigate links between variables by comparing them. Thoughtful choice of variables to compare is needed to add to your report. What are similarities and differences in trends and seasonal components between the variables. Discuss what you notice about the comparative data series - similarities, differences, possible relationships, reasons, causes, links etc EXEMPLARS: Use iNZight to produce a time series graph and add the trend line. Copy this into your report and discuss - Alcohol Consumptn: Data csv,| Word Worksheet | Google Doc class write up - Travel Destination Data csv | Word Write up | Google Doc class work - Travel Purposes: Data csv - Electricity Production: Data csv | (Website)

### Comparing variables over the same time period

Input the data as per normal

Hold down CTRL to select multiple data variables

then Compare Series using the 'Single-Plot' and 'Multi-Plot'

Discuss & compare in context

For each variable a Raw data graph with smoothed trend line, and seasonal effects are graphed with the same time.

The raw data graph also has 'trend + seasonal' (the hard to see green line) This shows what data values may be above or below average, and by how much.

Discuss what you notice about the comparative data series - similarities, differences, possible relationships, reasons, causes, links etc

Discuss and compare the Trend Lines.

Discuss and compare the Estimated Seasonal Effects (red line) and the Individual Seasonal Effects for each cycle (gray lines)