2. (8 marks) One rapid test for COVID- 19 being used on university campuses (the Sofia antigen test, see https://www.cdc.gov/mmwr/volumes/69/wr/mm695152a3.htm1 has a sensitivity (detection rate) of 80% and a specificity (1 the false positive rate) of 98.9% among symptomatic individuals and a sensitivity of 41.2% and a specicity of 98.4% among asymptomatic individuals. Say that the prevalence of COVID-l9 among asymptomatic and symptomatic individuals at a particular university is 0.7% and 0.2%, respectively. a. (3 marks) Explain what sensitivity and specicity mean in this context. b. (3 marks) Compute the negative predictive value (the probability that an individual who receives a negative test result does not have COVlD-l9) of the test for an asymptomatic individual. c. (2 marks) Compute the positive predictive value (the probability that an individual who receives a positive test result has COVID-19) of the test for a symptomatic individual. STAT 270 Assignment 2 Upload to Crowdmark by 5pm on Friday, October 8, 2021 Instructions: You must provide any code you use (final computed values are not sufcient). For every question, you should create a separate le (in .jpg, .pdf, or .png format) for uploading to Crowdmark. 1. (7 marks) Consider the egg production data from Assignment 1, Question 5. . (1 mark) Compute the sample correlation of egg weight and age of hen. b. (2 marks) Provide an interpretation of the sample correlation you computed in a). C. (2 marks) Considering the scatterplot of the data that you made for Assignment 1, is the sample correlation a good representation of the relationship between weight and age? Explain. (2 marks) Consider n new hens. Let the age (in weeks) and egg production (in g) of the I'm hen be xi and 325, respectively. Using the formula for sample correlation, show that the sample correlation between age and egg production for these hens remains the same if age is converted to days