In: Statistics and Probability
Consider the following hypotheses:
H0: μ = 1,800
HA: μ ≠ 1,800
The population is normally distributed with a population standard
deviation of 440. Compute the value of the test statistic and the
resulting p-value for each of the following sample
results. For each sample, determine if you can "reject/do not
reject" the null hypothesis at the 10% significance level.
(You may find it useful to reference the appropriate
table: z table or t
table) (Negative values should be
indicated by a minus sign. Round intermediate calculations to at
least 4 decimal places. Round "test statistic" values to 2 decimal
places and "p-value" to 4 decimal
places.)
Test statistic | p-value | |||
a. | x−x− = 1,850; n = 110 | (Click to select) Reject H0 Do not reject H0 | ||
b. | x−x− = 1,850; n = 280 | (Click to select) Reject H0 Do not reject H0 | ||
c. | x−x− = 1,650; n = 32 | (Click to select) Reject H0 Do not reject H0 | ||
d. | x−x− = 1,700; n = 32 | (Click to select) Reject H0 Do not reject H0 | ||
Solution :
= 1800
= 440
This is the two tailed test .
The null and alternative hypothesis is ,
H0 : = 1800
Ha : 1800
= 0.05
Test statistic z | p-value | ||||||
a | x -x=1850,n =110 |
Test statistic = z = ( - ) / / n = (1850-1800) /440 / 110 =1.19 |
0.2333 | Do not reject H0 | |||
b | x-x =1850 ,n =280 |
= ( - ) / / n = (1850-1800) /440 / 280 =1.90 |
0.0572 | Reject H0 | |||
c | x-x =1650, n =32 |
= ( - ) / / n = (1650-1800) /440 / 32 = -1.93 |
0.0538 | Reject H0 | |||
d | x-x =1700 , n= 32 |
= ( - ) / / n = (1700-1800) /440 / 32 = -1.29 |
0.1986 | Do not reject H0 |