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MODULE HYPOTHESIS TESTING
Step 1 of 1
Question 1 of 8 Points: 0 out of 10
According to Facebook’s self-reported statistics, the average Facebook user has 130 Facebook friends. For a statistics project
a student at Contra Costa College tests the hypothesis that CCC students will average more than 130 Facebook friends.
She randomly selects 3 classes from the schedule of classes and distributes a survey in these classes. Her sample contains
45 students.
Here are the null and alternative hypotheses for her study: H0: µ = 130, Ha: µ > 130.
What does µ represent in these hypotheses?
mean number of Facebook friends for the average user
mean number of Facebook friends for the CCC students in her sample
mean number of Facebook friends for CCC students
Not quite right: You are right that Facebook claims that the mean number of Facebook friends is 130
for the average user. But in this study the population of interest is CCC students. The correct answer
is C.
Question 2 of 8 Points: 0 out of 10
From her survey data, the statistics student calculates that the mean number of Facebook friends for her sample is 138.7
with a standard deviation of 79.3. She analyzed her data using a t-test and obtained a P-value of 0.23.
What conclusion can she draw from her data?
Nothing. The conditions for use of a t-test were not met. She cannot trust that the P-value is accurate for this
reason.
Even though 138.7 is larger than 130, it is not significantly larger than 130. In other words, the data do not
provide enough evidence to conclude that the mean number of Facebook friends of all CCC college students is
higher than 130.
138.7 is significantly larger than 130. In other words the data provide provide enough evidence to conclude
that the mean number of Facebook friends of all CCC college students is higher than 130.
Incorrect: Since the P-value is 0.23, the difference of 8.7 friends (138.7 – 130) is not statistically
significant. The correct answer is B.
Question 3 of 8 Points: 0 out of 10
According to Facebook’s self-reported statistics, the average Facebook user is connected to 80 community pages, groups,
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https://straighterline.acrobatiq.com/courseware/summative-assessment/sl_stats_v1/chkpt_hy...
https://www.coursehero.com/file/24825133/Hypothesis-Testing-for-a-Population-Mean-Checkpointpdf/ 9/3/2017