Question

Netflix stock prices have climbed since it was first introduced in 2002. A stock broker is interested in estimating the mean opening price for one share of Netflix stock. To do this, a random sample of 51 days from 2014 was taken, and the opening price of one share of the stock was recorded. The sample data is summarized in the StatCrunch output: Summary statistics: Column Mean Std. dev. Median Range Min Max Q1 Q3 Opening Price 51 409.6449 49.881232 428.19 166.49 317.16 483.65 365.66 448.69 Two-tail probability One-tail probability 0.20 0.10 0.10 0.05 0.05 0.025 0.02 0.01 0.01 0.005 1.310 1.309 1.306 1.303 1.301 1.299 1.296 1.293 1.290 1.697 1.694 1.690 1.684 1.679 1.676 1.671 1.665 1.660 1.658 2.042 2.037 2.030 2.021 2.014 2.009 2.000 1.992 1.984 2.750 2.738 2.725 2.704 2.690 2.457 2.449 2.438 2.423 2.412 2.403 2.390 2.377 2.364 2.358 2.678 2.660 2.643 2.626 2.617 120 1.289 1.980 • We are 98% confident that the true mean opening price for a share of Netflix stock is between $ and $ (Round the limits of your interval to 4 decimal places.) • In October 2014, HBO announced it will offer a stand-alone streaming service in 2015. Since the announcement, the mean opening price of a share of Netflix stock was $374.9019. Based on the interval above, does it seem that HBO's announcement has had an effect on Netflix stock? The HBO announcement seems to have had no effect on the price of Netflix stock. The price of Netflix stock has dropped since the announcement by HBO. The price of Netflix stock has risen since the announcement by HBO.

Answer 1

sample mean 'x̄=	409.645
sample size   n=	51.00
sample std deviation s=	49.881
std error 'sx=s/√n=	6.9848
test stat t ='(x-μ)*√n/sx=	58.5309

for 98% CI; and 50 df, value of t=		2.403
margin of error E=t*std error    =		16.786
lower bound=sample mean-E =		392.8586
Upper bound=sample mean+E =		426.4312

98% CI =between 392.8586 and 426.4312

since interval values are greater than 374.9019

The price of Netflix stock has risen since the announcement by HBO.