1.10 Multivariate Data Notes
Achievement
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You need to investigate a given multivariate data set using the statistical enquiry cycle to
make comparisons among groups in the population. Make sure that you are familiar with the
statistical enquiry cycle which involves:
o investigating data that has been collected from a survey situation
o posing an appropriate comparison question using a given multivariate data
o selecting and using appropriate display(s)
o giving summary statistics such as the five summary values (minimum, maximum,
median, quartiles)
o discussing features of distributions comparatively, such as shape, middle 50%, shift,
overlap, spread, unusual or interesting features. You will have to decide on the most
appropriate measures of centre/spread.
o communicating findings, such as informal inference and supporting evidence, in a
conclusion.
Achievement with merit
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Make sure that you can meet the criteria for achievement
You need to investigate a given multivariate data set using the statistical enquiry cycle with
justification.
This involves linking aspects of the statistical enquiry cycle to the context and the
population. Justification also involves making supporting statements, which refer to
evidence such as summary statistics, data values, trends or features of visual displays.
An understanding of variability or of context.
Achievement with excellence
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Make sure that you can meet the criteria for merit
You need to investigate a given multivariate data set using the statistical enquiry cycle with
statistical insight.
This means integrating statistical and contextual knowledge throughout the statistical
enquiry cycle, reflecting about the process, and may involve considering other explanations.
 When evaluating reports look at the following:
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other data that could be collected to improve the analysis
improvements to the method of data collection
better graphs that could be drawn, or other statistics that could be calculated ensuring your
conclusion shows an understanding of the context. (If you believe that you have made the
best choice of graph(s) and statistics explain why)
the validity of your conclusions
improvements to the question posed.