People remember when their horoscopes had an uncanny prediction— say, the prediction of a problem in love on the exact day of the breakup of a romantic relationship—and decide that horoscopes are accurate. Munro & Munro (2000) are among those who have challenged such a conclusion. They reported that 34% of students chose their own horoscope as the best match for them when the horoscopes were labeled with the signs of the zodiac, whereas only 13% chose their own horoscope when the predictions were labeled only with numbers and in a random order. Thirteen percent is not statistically significantly different from 8.3%, which is the percentage we’d expect by chance. 

a. What is the population of interest, and what is the sample in this study? 

b. Was random selection used? Explain your answer. 

c. Was random assignment used? Explain your answer. 

d. What is the independent variable and what are its levels? What is the dependent variable? What type of variables are these? 

e. What is the null hypothesis and what is the research hypothesis? 

f. What decision did the researchers make? (Respond using the language of inferential statistics.) 

g. If the researchers were incorrect in their decision, what kind of error did they make? Explain your answer. What are the consequences of this type of error, both in general and in this situation?