Experimenter bias refers to the phenomenon that data tends to comes out in the desired direction even for the most conscientious experimenters.A social psychologist is curious about this phenomenon.In a study, the psychologist tells a sample of students that they will be experimenters in study that investigates the impact of caffeine on cognition.The experimenters are told that all subjects will be given caffeine an hour before solving arithmetic problems.However, half of the experimenters are told that caffeine will lead to better performance and the other half are told nothing.The experimenters are then asked to grade the arithmetic problems.What can the psychologist conclude with anof 0.01?Below are the grades that they gave

told nothing leads to better performance

18 12

15 14

21 10

12 8

17 14

14 17

21 20

24 10

a)What is the appropriate test statistic?

---Select---

na

z-test

One-Sample t-test

Independent-Samples t-test

Related-Samples t-test

b)

Condition 1:

---Select---

grades

experimenter bias

told caffeine leads to better performance

told nothing

the phenomenon

Condition 2:

---Select---

grades

experimenter bias

told caffeine leads to better performance

told nothing

the phenomenon

c)Compute the appropriate test statistic(s) to make a decision aboutH₀.

(Hint: Make sure to write down the null and alternative hypotheses to help solve the problem.)

critical value =;test statistic =

Decision:

---Select---

Reject H0

Fail to reject H0

d)If appropriate, compute the CI. If not appropriate, input "na" for both spaces below.

[,]

e)Compute the corresponding effect size(s) and indicate magnitude(s).

If not appropriate, input and/or select "na" below.

d=;

---Select---

na

trivial effect

small effect

medium effect

large effect

r²=;

---Select---

na

trivial effect

small effect

medium effect

large effect