The homicide rate in Scotland fell last year to 99 from 115 the year before. Is this reported change really networthy?

The homicide rate in Scotland fell last year to 99 from 115 the year before. Is this reported change really networthy?



-Consider the homicides as independent; a Poisson distribution can be a reasonable model
-95% interval for the true homicide rate is 115±2×115−−−√=115±22=[94,137]115±2×115=115±22=[94,137]
-It's not reasonable to conclude that there has been a reduction in the true rate

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