Question

In 2015, 52% of adults had at least one subscription to a video streaming service. A survey was conducted recently in which 70% of 2,530 randomly selected adults indicated they have at least one subscription to a video streaming service. At the 0.01 significance level, we wish to test whether there is sufficient evidence to conclude that the percentage of adults who have at least one subscription to a video streaming service has increased from the 2015 value. The alternative hypothesis for this test of significance is unimodal, two-sided, one-sided, or bimodal?

Answer 1

In hypothesis testing regarding an increase in adults with at least one video streaming service subscription, the alternative hypothesis is one-sided. The null hypothesis assumes the proportion of subscriptions is 52% or less, while the alternative hypothesis suggests it has increased.

Step-by-step explanation:

The student's question relates to hypothesis testing in the context of proportions and specifically examines if there has been an increase in the number of adults with at least one subscription to a video streaming service. Since we are comparing the current proportion to a previous value (52% in 2015) to see if it has increased, the alternative hypothesis is one-sided. Our null hypothesis (H0) is that the proportion has not increased, that is, it is still 52% or less, whereas the alternative hypothesis (H1) is that the proportion has increased beyond 52%.

At the 0.01 significance level, we would calculate the test statistic for the sample proportion (70% of 2,530), compare it to the critical value from the z-table, and decide if there is sufficient evidence to reject the null hypothesis in favor of the alternative hypothesis.