2. Information:
-------------------------------------------------
unacc 1210 (70.023 %)
acc 384 (22.222 %)
good 69 ( 3.993 %)
v-good
65 ( 3.762 %)
3. Attribute values:
buying v-high(0), high(2), med(4), low(6)
maint v-high(0), high(2), med(4), low(6)
doors 2, 3, 4, 5-more(5)
persons 2, 4, more(6)
lug_boot small(0), med(1), big(2)
safety low(0), med(1), high(2)
class
unacc(0), acc(2), good(4), v-good(6)
4. Database: 1728 instances.
Car Database file has 1728 - 20 = 1708 instances. The data required for 100% accuracy is:
Class
#Required
#Actual
Accuracy
Instance
Instance Expected
0 = unacc 800 1210 100%
2 = acc 800 384
4 = good 800 69
6 = v-good 800 65
Total 3200 1728
The most important feature here is to understand the DecisionMaker will be expected to predict class 0 (and only class 0) with 100% accuracy. The data can be used to estimate class 2. For class 4 and 6, the DM can be used at most for educated guess.
As we will see, the DecisionMaker 2.5 will have an accuracy rate of 100% for class 0. Below are the first 10 instances:
0 0 2 2 0 0 0
0 0 2 2 0 1 0
0 0 2 2 0 2 0
0 0 2 2 1 0 0
0 0 2 2 1 1 0
0 0 2 2 1 2 0
0 0 2 2 2 0 0
0 0 2 2 2 1 0
0 0 2 2 2 2 0
0 0 2 4 0 0 0
Below are the last 20 instances, which will be used to test the DecisionMaker 's accuracy:
6 6 5 2 2 1
0
6 6 5 2 2 2
0
6 6 5 4 0 0
0
6 6 5 4 0 1
2
6 6 5 4 0 2
4
6 6 5 4 1 0
0
6 6 5 4 1 1
4
6 6 5 4 1 2
6
6 6 5 4 2 0
0
6 6 5 4 2 1
4
6 6 5 4 2 2
6
6 6 5 6 0 0
0
6 6 5 6 0 1
2
6 6 5 6 0 2
4
6 6 5 6 1 0
0
6 6 5 6 1 1
4
6 6 5 6 1 2
6
6 6 5 6 2 0
0
6 6 5 6 2 1
4
6 6 5 6 2 2
6
5. Results.
Click "Integer/+ Predict" to get the following answer file:
=================== End ==========================
6 6 5 2 2 1
Possibility Confidence*Probability
0 37076
------------------------------------------------------
0
6 6 5 2 2 2
Possibility Confidence*Probability
0 35858
------------------------------------------------------
0
6 6 5 4 0 0
Possibility Confidence*Probability
0 27976
------------------------------------------------------
0
6 6 5 4 0 1
Possibility Confidence*Probability
0 18207
2 16790
------------------------------------------------------
1
6 6 5 4 0 2
Possibility Confidence*Probability
0 12485
2 8549
4 14800
------------------------------------------------------
2
6 6 5 4 1 0
Possibility Confidence*Probability
0 34997
------------------------------------------------------
0
6 6 5 4 1 1
Possibility Confidence*Probability
0 22119
2 9388
4 13312
------------------------------------------------------
2
6 6 5 4 1 2
Possibility Confidence*Probability
0 14960
2 11261
6 14772
4 4520
------------------------------------------------------
3
... ...
=================== End ==========================
6. Analysis
Remember the 4 classes and what each class stand for:
class
code
-------------------------------------------------
unacc
0
acc
2
good
4
v-good
6
# Correct Answer Predicted Answer
1
0
0, 100%
2
0
0, 100%
3
0
0, 100%
4
2
2, 48%
5
4
4, 41%
6
0
0, 100%
7
4
0, 49%; 4, 23%; wrong
8
6
0, 36%; 6, 32%; wrong
As expected, the classification for class 0 (unacceptable) is 100% accurate.
Class 4 and 6 do not have enough instances (69 instances of class 4 and
65 instances of class 6), thereby severely limiting the DecisionMaker
's ability to provide you with 100% accuracy.