Question

Question 29 options: A researcher is studying the effectiveness of a new “brain training” game for Android phones, which the game’s developer says can improve memory. The game involves watching a series of cartoon animals run across the screen and tapping whenever the same animal appears twice. The researcher designs an experiment in which 20 participants (the memory group) play the game for 1 hour a day for a week. Another 20 participants (the non-memory group) plays a game with similar graphics but no memory demand for 1 hour a day for a week. At the end of the week, both groups complete a standardized memory test on their phone. Participants in the memory group had a mean standardized memory test score of 59.5338 with a standard deviation of 4.1700 and a SS of 330.3959. At the end of the week one of the participants in the non-memory group reports that he lost his phone at a bar over the St. Patrick’s day weekend and all his data are lost. For the remaining participants in the non-memory group, the mean score on the standardized memory task was 57.0333 with a standard deviation of 5.5714 and a SS of 558.7226. Conduct a hypothesis test at the alpha = 0.05 level? Fill in each of the blanks below. What type of test should you use (z-test; one sample t-test; independent samples t-test; or power analysis): Step 1: State the null hypothesis (just the null, no need to state the alternative; for μ1 simply type "mu1"): Step 2: what value defines the boundary of the positive critical region (enter a positive number with 5 decimal places using only the keys "0-9" and "."): Step 3: Calculate and then enter the observed value of the appropriate statistic (enter a number with 5 decimal places using only the keys "0-9" and "."): Step 4: Do you reject the null hypothesis (type yes or no): Finally, write one sentence to interpret the result of the hypothesis test in terms of the original research question (i.e., what does your result mean):

Answer 1

What type of test should you use (z-test; one sample t-test; independent samples t-test; or power analysis):

independent samples t-test

Step 1: State the null hypothesis (just the null, no need to state the alternative; for μ1 simply type "mu1"):

H0: mu1 = mu2

Step 2: what value defines the boundary of the positive critical region (enter a positive number with 5 decimal places using only the keys "0-9" and "."):

1.68595

Step 3: Calculate and then enter the observed value of the appropriate statistic (enter a number with 5 decimal places using only the keys "0-9" and "."):

1.60689

Step 4: Do you reject the null hypothesis (type yes or no): Finally, write one sentence to interpret the result of the hypothesis test in terms of the original research question (i.e., what does your result mean):

no

We cannot support the claim about the effectiveness of the new “brain training” game for Android phones, which the game’s developer says can improve memory.

1	2
59.5338	57.0333	mean
4.17	5.5714	std. dev.
20	20	n
	38	df
	2.5005000	difference (1 - 2)
	24.2146990	pooled variance
	4.9208433	pooled std. dev.
	1.5561073	standard error of difference
	0	hypothesized difference
	1.68595	critical value
	1.60689	t
	.0582	p-value (one-tailed, upper)