It can be difficult to motivate preschoolers to practice writing letters. Perhaps a reward system will do the trick, but what type of rewards work? Here are the data from a randomized experiment that compared three treatments among children in preschool. A “success” means that the child completed a worksheet in which they traced the entire alphabet in one sitting. Group 1 2 3 Reward Choice of a small toy Choice of candy Promise of immediate recess Subjects 20 24 16 Successes 13 18 10 (a) Which chi-square test is appropriate in this setting? Explain your reasoning.
(b) State the appropriate hypotheses for performing a chi-square test in this setting.
(c) The chi-square test statistic is x² = 0.847. Calculate the P-value.
(d) Interpret the P-value.
(e) What conclusion would you draw?