11-2 Inference aplet
Inference aplet’s SYMB view keys
The table below summarizes the options available in 
Symbolic view.
If you choose one of the hypothesis tests, you can choose 
the alternative hypothesis to test against the null 
hypothesis. For each test, there are three possible choices 
for an alternative hypothesis based on a quantitative 
comparison of two quantities. The null hypothesis is 
always that the two quantities are equal.Thus, the 
alternative hypotheses cover the various cases for the two 
quantities being unequal: <, >, and ≠.
In this section, we will use the example data for the Z-Test 
on 1 mean to illustrate how the aplet works and what 
features the various views present.
Hypothesis 
Tests
Confidence Intervals
Z: 1 μ, the Z-Test 
on 1 mean
Z-Int: 1 μ, the confidence 
interval for 1 mean, based on 
the Normal distribution
Z: μ
1
 – μ
2
, the 
Z-Test on the 
difference of two 
means
Z-Int: μ
1
 – μ
2
, the confidence 
interval for the difference of 
two means, based on the 
Normal distribution
Z: 1 π, the Z-Test 
on 1 proportion
Z-Int: 1 π, the confidence 
interval for 1 proportion, 
based on the Normal 
distribution
Z: π1 – π2, the 
Z-Test on the 
difference in two 
proportions
Z-Int: π1 – π2, the confidence 
interval for the difference of 
two proportions, based on the 
Normal distribution
T: 1 μ, the T-Test on 
1 mean
T-Int: 1 μ, the confidence 
interval for 1 mean, based on 
the Student’s t-distribution
T: μ
1
 – μ
2
, the T-
Test on the 
difference of two 
means
T-Int: μ
1
 – μ
2
, the confidence 
interval for the difference of 
two means, based on the 
Student’s t-distribution
hp40g+.book  Page 2  Friday, December 9, 2005  12:27 AM