e? what is the state alternative hypothesis?

Does caffeine improve exam performance? Suppose all students in the 8:30 section of a course are given a "treatment" (two cups of coffee) and all students in the 9:30 section are not permitted to have any caffeine before a mid-term exam. The response variable in this study is .. two cups of coffee. exam performance. teacher's performance. a O b O d class attendance.

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Which of the following is not true regarding internal validity and external validity1. It’s OK for a study to have low internal validity, but it’s not OK for a study to have low external validity 2. It’s OK for a study to have low external validity, but it’s not OK for a study to have low internal validity 3. Internal validity is the foundation for external validity4. External validity is the foundation for internal validity

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You watch people exiting Dodgers stadium after a game and you write down the number of males and the number of females that exit the stadium past you during the 20 minutes that you spend watching. You assumed that there would be a perfectly equal number of males and females attending a Dodgers game, but you look at the number of males and females that you actually counted, and you see if you still think that is actually true. What kind of hypothesis test would allow you to do this? a. One-Factor, Independent-Measures ANOVA b. Two-Factor ANOVA c. Correlation/Regression d. Chi-Square Goodness of Fit

USE THE 8-STEP HYPOTHESIS TESTING Refer to the study by Carter et al. [A-9], who investigated the effect of age at onset of bipolar disorder on the course of the illness. One of the variables studied was subjects' family history. Table 3.4.1 shows the frequency of a family history of mood disorders in the two groups of interest: early age at onset (18 years or younger) and later age at onset (later than 18 years). Family History of Mood Disorders Early ≤ 18(E) 28 19 41 53 Later > 18 (L) 35 38 44 60 141 Total 63 57 85 113 Negative (A) Bipolar disorder (B) Unipolar (C) Unipolar and bipolar (D) Total 177 318 Source: Tasha D. Carter, Emanuela Mundo, Sagar V. Parkh, and James L. Kennedy, "Early Age at Onset as a Risk Factor for Poor Outcome of Bipolar Disorder," Journal of Psychiatric Research, 37 (2003), 297-303. Can we conclude on the basis of these data that subjects 18 or younger differ from subjects older than 18 with respect to family histories of mood disorders? Let a = .05.

In general terms, what does an alternative hypothesis (H1) say?   Group of answer choices There is a treatment effect in the sample There is no treatment effect in the population There is a treatment effect in the population There is no treatment effect in the sample