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Casewise Interpretation

This analysis has a rotated solution and extracts 5 factors (as in the previous example 3).In the following plot cases are labelled by their region.

Plot of case scores against factors 1 and 2.[D]

The following table is count of the number of cases, for each region, which are above and below 0 (above and below the factor means).

Region

Factor 1
Below 0

Factor 1
Above 0

Factor 2
Below 0

Factor 2
Above 0

1

26

13

2

37

2

14

22

1

35

3

7

5

8

4

4

26

4

22

8

5

14

26

26

14

6

15

21

20

16

8

1

6

6

1

9

3

11

13

1

10

3

11

13

1

11

2

11

11

2

12

9

2

10

1


The rotated loadings are shown below. All absolute loadings < 0.3 have been blanked to ease interpretation.

Variable

Factor1

Factor2

Factor3

Factor4

Factor5

MaxAlt

0.942

        

MeanAlt

0.807

-0.310

0.323

    

SDAlt

0.848

    

0.418

  

MeanSlope

0.778

    

0.498

  

Mire

      

-0.844

  

Heathland

  

-0.403

0.355

0.517

  

WetHeath

        

-0.880

Deer

0.326

  

0.570

0.400

  

Sheep

    

-0.804

-0.331

  

Cattle

  

-0.923

      

NPP

    

-0.722

  

-0.434

Grazed

  

-0.930

      
           


1
Interpreting the factor score plot

Fill in the gaps

Cases from regions 9,10 and 11 tend to have habitat that is at a altitude and slope than average. They also tend to have more . Conversely, most cases from region have more -lying land which is also relatively . Cases from regions 5 & 6 occur above and below the for factor 1. Scores on factor 2, which is related to grazing, tend to mainly above or below the mean, except for regions. In particular, regions 1 and 2, have cattle densities. In the next section enter your answer as top left, bottom right, etc. Habitat for the cases in the four quadrants are best described as: relatively high and steep with relatively large numbers of cattle (presumably on the lower ground) ; relatively low-lying, with larger numbers of cattle ; low-lying with few cattle ; relatively high, steep ground with few cattle .

Cases from regions 9,10 and 11 tend to have habitat that is at a higher altitude and greater slope than average. They also tend to have more deer. Conversely, most cases from region 12 have more low-lying land which is also relatively flat. Cases from regions 5 & 6 occur above and below the mean for factor 1. Scores on factor 2, which is related to cattle grazing, tend to mainly above or below the mean, except for 3 regions. In particular, regions 1 and 2, have low cattle densities. In the next section enter your answer as top left, bottom right, etc. Habitat for the cases in the four quadrants are best described as: relatively high and steep with relatively large numbers of cattle (presumably on the lower ground) bottom right; relatively low-lying, with larger numbers of cattle bottom left; low-lying with few cattle top left; relatively high, steep ground with few cattle top right.

There are two important rules to understand. (1) The mean factor scores are 0, therefore negative factors are below average while positive scores are above average. (2) The loadings are correlation coefficients. If a correlation is positive the value of the variable will tend to increase and the factor scores become more positive. If a coefficient is negative, the value of the variable will tend to decrease as the factor score becomes more positive.Check your answer