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Remember: You Have to run iNZight TWO times! The iNZight tips page has information on ordering, removing, grouping, recategorising, & exporting data, and creating variables, adding variables to create box plots and show summary statistics. (Adding another variable can also provide more information) ***Manipulating data in Excel first can be a good idea, especially to combine groups together notes Class notes




Ensure you have the latest version of iNZight downloaded free download and videos on how to get started Run iNZight 

1) To Analyse the SampleRun iNZight normally, import data Decide on your variable, and what your two groups are (see iNZight tips page for ordering, removing, grouping, recategorising, & exporting data, and creating variables) Add variables to create box plots and show summary statistics. (Adding another variable can also provide more information (iNZight tips page) 

Input Data Not sure how to Import Data? Find out here... REMEMBER: If you upload your own data it MUST be in a .csv file, with variable notation, no commas, no variable definitions etc 

Make a dot plot & Box plot Drag ONE VARIABLE and ONE Group to the 'variables' Note: You may want to manipulate the data in excel first, eg If therre are multiple groups thencombining some together so there is only two groups would be a good idea. 

Get SAMPLE SUMMARY statistics
Now DISCUSS the SAMPLE STATISTICS & DOT plot & BOX plot


2) Bootstrapping using iNZightDifference between two Population Groups 

iNZight Bootstrap confidence intervals 

How to compare two groups and answer "Is the median on Blah different from the median of Blah in the population of Blah? Import data which has two categories The two columns of data  one is measured data and the other is the group 

Add variables (variable 1 is primary variable, Variable 2 is group) 

Analyse 

Discuss the dot plots for the sample groups. The Arrow represents the difference between the medians of the two sample groups Remembering that the samples vary each time. Does the population medians also differ? 

Analyse, record my choices The differences between the pairs of data values is the 'sample' Bootstrap resamples are taken from this 'sample' of differences. 

Resample You can watch one animation to get the idea.. or resample 1000 times to see the variation in the resampled medians.
The top dot plot is the original sample differences The bottom dot plot is of a single resample of size 'n' with replacement. The differences in the resample medians is recorded 


Bootstrap Distribution You can watch one animation to get the idea.. then Resample 1000 times to see the bootstrap distribution of the differences between repeated resamples from each group Show the CI to see the Bootstrap confidence interval. 

Interpret what you see Multiple resamples build up a distribution of differences between the means (see the compare populations page if you are not sure) How do we interpret these results? What does this tell us? You MUST discuss the relative position of 0 and what this means with respect to the two population medians (or means)
