At time t = 0, 19 identical components are tested. the lifetime distribution of each is exponential with parameter λ. the experimenter then leaves the test facility unmonitored. on his return 24 hours later, the experimenter immediately terminates the test after noticing that y = 13 of the 19 components are still in operation (so 6 have failed). derive the mle of λ. [hint: let y = the number that survive 24 hours. then y ~ bin(n, p). what is the mle of p? now notice that p = p(xi ≥ 24), where xi is exponentially distributed. this relates λ to p, so the former can be estimated once the latter has been.] (round your answer to four decimal places.)

Ascientist studied a population of workers to determine whether verbal praise and/or tangible rewards affect employee productivity. in the study, some workers were offered verbal praise, some were offered tangible rewards (gift cards, presents, and some were offered neither. the productivity of each participant was measured throughout the study by recording the number of daily tasks completed by each employee. which inference might the scientists make based on the given information? a.) the number of daily tasks completed by each employee may influence the dependent variable, which is whether the employee receives verbal praise, tangible rewards, or neither. b.) verbal praise and/or tangible rewards may influence the independent variable, which is the number of daily tasks completed by each employee. c.) verbal praise and/or tangible rewards may influence the dependent variable, which is the number of daily tasks completed by each employee. d.) the dependent variables, which are verbal praise and tangible rewards, may influence the number of daily tasks completed by each employee.