User Manual

examples

Example A consumer group is testing camp stoves. To test the heating capacity

of a stove they measure the time required to bring 2 qt of water from

F to boiling (at sea level). Two competing models are under

consideration. 36 stoves of each model were tested and the following

results were obtained.

Model 1: mean time

o1 = 11.5min; standard deviation σ1= 2.4min

Model 2: mean time

o2 = 10 min; standard deviation σ2= 3 min

Is there any difference between the performances of these two

models? (Use a 5% level of significance.)

Procedure

1 m STAT2

2 3(TEST) b(Z)c(2-Smpl)

3 2(VAR) c

1(≠) c

c.ew

bb.fw

dgw

baw

dgw

1(None) c

4 1(CALC)

6(DRAW)

Result Screen

Since P = 0.01914957 < 0.05 (level of significance), we reject the null hypothesis µ1-µ2 =0

and conclude the performances of the two models are different.