Biostatistics

Fernando et al. (2003) studied drug-sharing among injection drugs users in the South Bronx in New York City. Splitting a bag – a practice where heroin is shared between two people after dissolving it in a common cooker prior to injection– is a known high risk factor for HIV exposure.  Interviews with drug users in a residential treatment facility provided the following information.   Gender Have you split drugs? Total Yes (Y) No (N) Male (M) 390 321 711 Female (F) 179 131 310 Total 569 452 1021  What is the probability that a person chosen at random will have split drugs? What is the probability that a person chosen at random is not female? What is the probablity that a person has split drugs given they are a male? WHat is the probablility that someone chosen at random will be a female or will not have split drugs? Given taht someone has split drugs, what is the probablity that they are female?Â