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A Type II error occurs when a researcher concludes

With alpha = .05, what is the probability of making a Type I error?

[Example continued…] The average YouTube user spends 40 minutes per session, using YouTube (μ = 40), and σ is unknown. Test whether ARC students who are YouTube users (n = 16, M = 45, SS = 6000) differ from the average YouTube user on number of minutes spent using YouTube per session. α = .05. Based on this data, we could be making a  ____ error.  Based on this data, we should conclude that ARC students ______ from the average YouTube user. 

[Example continued…] The average YouTube user spends 40 minutes per session, using YouTube (μ = 40), and σ is unknown. Test whether ARC students who are YouTube users (n = 16, M = 45, SS = 6000) differ from the average YouTube user on number of minutes spent using YouTube per session. α = .05. The correct APA format for the result would be

[Example continued…] The personality trait of “Conscientiousness” (someone who is organized, responsible, and can control their impulses) has μ = 120 and σ =9. Test whether ARC students (n = 9, M = 126) differ on Conscientiousness. α = .05. What type of error could you be making?

[Example continued…] The average YouTube user spends 40 minutes per session, using YouTube (μ = 40), and σ is unknown. Test whether ARC students who are YouTube users (n = 16, M = 45, SS = 6000) differ from the average YouTube user on number of minutes spent using YouTube per session. α = .05. s2 =

[example continued…] Is there a difference among the 3 treatments in the table below?  Test using α = .05 Treatment A Treatment B Treatment C 2 3 2 ∑X2 = 280 2 3 4 G = 60 3 4 5 N = 15 3 5 6 k = 3 5 5 8 SS1 = 6 SS2 = 4 SS3 = 20   F = ______  (test statistic, F Ratio)

[example continued…] A normal distribution has μ = 9 and σ = 2. What is the probability of a score less than 6 from this distribution, p(X < 6)?

[example continued…] Below is data for two variables, X and Y.  Answer the questions that follow.  X Y X-MX Y-MY (X-MX)2 (Y-MY)2 (X-MX)(Y-MY) 3 3 -2 -1 4 1 2 4 3 -1 -1 1 1 ___ 6 4 1 ___ 1 0 0 7 6 2 2 ___ 4 4   Positive or negative correlation?

[example continued…] Does training in stress reduction make a difference for student success?  15 students received training (M1= 88, SS1= 400) and 15 students did not (M2= 82, SS2= 440). Test using α = .05   t =     (test statistic) =