AS 2.9 Inference Checklist
Problem/Question (INTRODUCTION)
General introduction statement  what the report is about
 Variables defined with units
 Groups are defined.
 Population defined (and any assumptions)
 Formed a Comparative Research Question (Variable, groups, 'median', direction, population)
 A prediction is make: ‘I think that...’
 Reason why making your prediction: Why ‘I think that...’
Plan
Use iNZight to:

Take a random sample,

Analyse the sample
 Make a box & dot plot
 Display the informal confidence interval bars (save the display image)
Data / Display
 Did you have to ‘clean’ the data’ (discuss)
 Comment on the sampling method,
 Comment on the appropriateness of the sample size.
Analysis / Discussion
Discussion of the SAMPLE:

Sample statistics comparing two groups.
 Distribution (dot plots) of the two groups symmetry, skew, outliers, gaps, clusters
 Box plots (Initial interpretation, Shape, Centre (middle 50%), Unusual aspects, Spread, Shift / Overlap)
The discussion needs be in context at all levels.
Also consider possible reasons or causes of these features (in the context)
‘I notice ... I expected ... I was surprised that...’
Discussing of sampling variability, including the variability of estimates (ESSENTIAL for Achieve)
Informal Confidence Intervals
 Discussion of what each informal confidence interval means
 Discussion of informal confidence interval overlap / or not
(in context & referring back to the population and how sure you are)
'I can be reasonably sure that...'
Conclusion
 Answer your research question by referring to your graphs, analysis and informal confidence interval.
 Make a conclusion about the population medians based on their samples taken from the population.
 Discuss errors, bias, omissions, improvements, further research...
 Discuss sampling variability, including the variability of the population estimates.
 An understanding relating to sampling variability and variability of estimates must be evident.
 Discuss the effect of different sample sizes
 Be sure to be clear when you are discussing the sample and when you are discussing the population estimate.
