Understand reasons to prefer the k-means method to linkage methods in cluster analysis.
- [Instructor] In Excel, it's very easy to set up…the confusion table so you can determine exactly…a degree of agreement and disagreement, or confusion,…in how the analysis classifies the records according…to clusters and the known species.…I'll create one right now.…Begin by selecting a cell in the region…that contains the input data.…Then click the Ribbon's Insert tab…and click on Pivot Table in the Tables group.…
The Create Pivot Table dialog box appears.…I generally accept the defaults,…except that I click the Existing Worksheet…under Choose where you want…the PivotTable report to be placed.…Also, I click cell J2 as the pivot table's location.…I find it more convenient to have the pivot table…located on the worksheet…that contains the input data when space permits.…Then I click OK.…In the PivotTable Fields pane, I click Record IDs…and drag it down to the ROWS area at the bottom of the pane.…
Then I click the Clusters item…and drag it into the COLUMNS area.…I click the Clusters item again…and drag it into the SUM VALUES area.…
In this course, Conrad Carlberg explains how to carry out cluster analysis and principal components analysis using Microsoft Excel, which tends to show more clearly what's going on in the analysis. Then he explains how to carry out the same analysis using R, the open-source statistical computing software, which is faster and richer in analysis options than Excel. Plus, he walks through how to merge the results of cluster analysis and factor analysis to help you break down a few underlying factors according to individuals' membership in just a few clusters.
- Reviewing the problems created by an overabundance of data
- Understanding the rationale for clustering and principal components analysis
- Using Excel to extract principal components
- Using R to extract principal components
- Using R for cluster analysis
- Using Excel for cluster analysis
- Setting up confusion tables in Excel
- Using cluster analysis and factor analysis in concert