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If exactly 1% of the t distribution is located in the tail beyond t = 2.650, how many degrees of freedom are there? df = [color1]

For the next eleven questions (1 -11), you will be conducting a hypothesis test and reporting your findings.   Horvath et al. (2017) revealed that binge-watchers reported enjoying a TV show significantly less than people who watched the same show on a daily or weekly schedule. To examine this phenomenon, you randomly assigned participants to watch an entire TV series in the lab during either daily one-hour sessions or a single binge session. Participants were then asked to rate their enjoyment of the series on a scale of 0 – 100. Their ratings are in the table below. Use a two-tailed test with α = .05 to examine the impact of binge-watching on the enjoyment of the show.

Several mistakes were made when reporting the findings. What are they? Binge-watching appears to significantly diminish the enjoyment of watching a TV show, t(9) = 2.93, p < .05, d = 1.04. On average, those who watched the show in a single binge session (M = 92, SD = 6.67) enjoyed the show less than those who watched it on a daily basis (M = 79, SD = 7.31).

A new over-the-counter cold medication includes a warning label stating that it “may cause drowsiness” and therefore, it may affect people’s reaction time, which is known to be µ = 206 milliseconds. To evaluate this effect, you obtained a sample of n = 9 people and gave them the new cold medication. One hour later, you measured the reaction time for each individual. The average reaction time for the sample is M = 200  milliseconds with SS = 648. Using a one-tailed test, what decision should be made?

Five hundred confidence intervals, each having level of confidence of 90% were computed for a population mean µ. Approximately how many of the confidence intervals would not capture µ?  [color1]

When comparing two groups using an independent samples t-test, you must ensure that these groups are equal in size. Otherwise, you cannot use this t-test.

What conclusion can you draw from the result of the t-test presented below?  

There are two sources of error contributing to the standard error in the denominator of the independent samples t-test equation.

How do sample size and sample variance influence measures of effect size, such as Cohen’s d?

Do college students preform worse in online courses? To answer this question, a researcher compared the test scores of students enrolled in online vs. in person class. Their scores are presented in a table below. Using a one-tailed test with α = .05, what conclusion should be made?