a. Define the parameter of interest in the context of the study and assign a symbol to it.
b. State the null hypothesis and the alternative hypothesis using the symbol defined in part (a).
c. What is the observed proportion of times the infants picked the helper toy? What symbol should you use to represent this value?
d. Use an applet to generate the null distribution of the proportion of “successes.” Determine the standardized statistic for the observed sample proportion of “successes.” Show your work.
e. Interpret the standardized statistic in the context of the study. (Hint: You need to talk about the value of your observed statistic in terms of standard deviations assuming ______ is true.)
f. Based on the standardized statistic, state the conclusion that you would draw about the research question of whether such 10-month-old infants have a genuine preference for the helper toy.