In: Statistics and Probability
In a random sample of males, it was found that 20 write with their left hands and 222 do not. In a random sample of females, it was found that 64 write with their left hands and 439 do not. Use a 0.01 significance level to test the claim that the rate of left-handedness among males is less than that among females. Complete parts (a) through (c) below.
n1 = 20 + 222 = 242
n2 = 64 + 439 = 503
x1 = 20, x2 = 64
= 0.01
= 0.083, = 0.127
= 0.113
The null and alternative hypothsis is
H0: p1=p2
H1: p1<p2
Calculate the test statistic.
test statistics: z = -1.80
Calculate the P-value.
P-Value = P(Z < -1.80)
using normal z table we get
P(Z < -1.80)= 0.0357
P-value = 0.036
decision rule is
Reject Ho if ( P-value ) ( )
here, ( P-value= 0.036) > ( = 0.01)
Hence, we can say,
Do not reject null hypothesis.
Conclusion:
The P-value greater than the significance level of = 0.01, so fail to reject the null hypothesis. There is not sufficient evidence to support the claim that the rate of left-handedness among males is less than that among females.