# Section 5.1.pptx - Section 5.1 Hypothesis Tests Using...

• 31

This preview shows page 1 - 9 out of 31 pages.

Statistics: Unlocking the Power of DataLock5Hypothesis Tests Using Normal DistributionsSection 5.1
Statistics: Unlocking the Power of DataLock5Use test statistic language
Statistics: Unlocking the Power of DataLock5Question of the DayHow do Malaria parasites impact mosquito behavior?
Statistics: Unlocking the Power of DataLock5Malaria Parasites and MosquitoesMosquitos were randomized to either eat from a malaria infected mouse (exposed group) or a healthy mouse (control group)After infection, the parasites go through two stages:1)Not yet infections (Days 1-8)2)Infectious (Days 9 – 28)Response variable: whether the mosquito approached a human (in a cage with them)Does this behavior differ by exposed vs control? Does it differ by infection stage?Cator LJ, George J, Blanford S, Murdock CC, Baker TC, Read AF, Thomas MB. (2013). Manipulationwithout the parasite: altered feeding behaviour of mosquitoes is not dependent on infection with malaria parasites. Proc R Soc B 280: 20130711.
Statistics: Unlocking the Power of DataLock5Malaria Parasites and MosquitoesMalaria parasites would benefit if:Mosquitos approached humans less often after being exposed, but before becoming infectious, because humans are risky (so more likely to stay alive)Mosquitoes approached humans more often after becoming infectious, to pass on the infectionDoes infecting mosquitoes with Malaria actually impact their behavior in this way?
Statistics: Unlocking the Power of DataLock5Before InfectiousWe’ll first look at the mosquitos before they become infectious (days 1–8). Explanatory variable: Exposed or control Response variable: whether approached human What are the relevant hypotheses?pC: proportion of controls to approach humanpE: proportion of exposed to approach humanH0: pE= pCHa: pE< pC
Statistics: Unlocking the Power of DataLock5Data: Before Infectious
Statistics: Unlocking the Power of DataLock5Randomization Testp-valueobserved statistic