Probability: What is it and how do you calculate it?

Question 1 

Question 2 

Part A 

The probability of being left-handed is calculated by taking the total number of left-handed individuals and dividing it by the total number of study participants. In this case, the probability is = 

Part B 

The probability of choosing a left-handed female is calculated by dividing the total number of left-handed female individuals by the total number of female individuals. The probability is 

Part C 

The odds ratio of selecting a left-handed female is computed by dividing the probability of choosing a left-handed by the probability of not choosing a left-handed female. Resultantly, the odds ratio is 

Part D 

The relative risk of selecting a left-handed female is computed by dividing the of choosing a left-handed female by the probability of selecting a left-handed male. In this respect, the relative risk is 

Question 3 

There are similarities and differences between my study and the assigned studies. In all studies, the majority of individuals are right-handed, and, in this case, the probability of being right-handed is higher than being left-handed. In my study, the probability of being left-handed is significantly higher than that indicated in the assigned study conducted by Orr (2001), which mentions that the probability of being left-handed is 10 to 13 percent. My study shows that the probability of being left-handed is 40 percent. My study’s results also differ from those obtained by Loffing et al. (2012), who examined the left-handed nature of professionals and amateurs in tennis. According to the authors, there is a greater probability of left-handedness among males compared to females. On the contrary, my study illustrates that there is an equal probability for left-handedness among males and their female counterparts, given that their probability for each is 0.5. 

References 

Loffing, F., Hagemann, N., & Strauss, B. (2012). Left-handedness in professional and amateur tennis.  PLoS One ,  7 (11), e49325. https://doi.org/10.1371/journal.pone.0049325 

Orr, T. B. (2001). Being a lefty is all right!  Current Health 2 ,  28 (2), 12-13.