More people are using social media to network rather than ph

More people are using social media to network, rather than phone calls or e-mails (US News & World Report, October 20, 2010). From an employment perspective, jobseekers are no longer calling up friends for help with job placement, as they can now get help online. In a recent survey of 150 jobseekers, 67 said they used LinkedIn to search for jobs. A similar survey of 140 jobseekers, conducted three years ago, had found that 58 jobseekers had used LinkedIn for their job search. Use Table 1.

Let p₁ represent the population proportion of recent jobseekers and p₂ the population proportion of job seekers three years ago. Let recent survey and earlier survey represent population 1 and population 2, respectively.

Calculate the value of the test statistic. (Round intermediate calculations to 4 decimal places and final answer to 2 decimal places.)

Solution

Null, less OR equal are now using LinkedIn to search for jobs Ho: p1 p2 0
Alternate, more people are now using LinkedIn to search for jobs H1: p1 -p2 > 0
Test Statistic
Sample 1 : X1 =67, n1 =150, P1= X1/n1=0.4467
Sample 2 : X2 =58, n2 =140, P2= X2/n2=0.4143
Finding a P^ value For Proportion P^=(X1 + X2 ) / (n1+n2)
P^=0.431
Q^ Value For Proportion= 1-P^=0.569
we use Test Statistic (Z) = (P1-P2)/(P^Q^(1/n1+1/n2))
Zo =(0.447-0.4143)/Sqrt((0.431*0.569(1/150+1/140))
Zo =0.5564
| Zo | =0.5564
Critical Value
The Value of |Z | at LOS 0.05% is 1.645
We got |Zo| =0.556 & | Z | =1.645
Make Decision
Hence Value of |Zo | < | Z | and Here we Do not Reject Ho
P-Value: Right Tail -Ha : ( P > 0.5564 ) = 0.28896
Hence Value of P0.05 < 0.28896,Here We Do not Reject Ho

We don\'t have evvidence to indicate that more people are now using LinkedIn to
search for jobs as compared to three years ago.

[ANSWER]
a. H0: p1 p2 0; HA: p1 p2 > 0
b. Zo =0.5564
c. Critical Value, LOS 0.05% is 1.645
d. Do not reject H0; there is no increase in the proportion of people using LinkedIn