Concerns have been raised about the effectiveness of this seasons flu vaccination after it was noticed that a high proportion of people with severe illness have been vaccinated. Data has been collected on the following attributes of the flu sufferers (see the file FluVac.xls)

1. Based on your investigation of the data set create two well-formatted tables that illustrate some important features of the data. Your tables should have informative labels and a readable number of decimal places. Each table should include an informative caption. [8 marks]

2. With reference to the tables you have made, is there evidence that the vaccine is effective or not? [4 marks]

One reason why it is difficult to ascertain cause and effect based on association is that there may be confounding variables, these are variables which are related to both the explanatory (independent) and response (dependent) variable. In the data set presented here which variable is explanatory, which is response, and which is confounding? [3 marks]

Imagine that the data is this study has been collected by surveying people who present at hospital with flu symptoms. Can you identify any potential biases in this form of data collection that might influence our ability to answer our key question? How else could data be collected to avoid this bias? [5 marks]

3643653663673683693703713723733743753763773783793803813823833843853863873883893903913923933943952548406193517316256777693651332466244226944275518094424671949051unvaccinatedunvaccinatedunvaccinatedunvaccinatedvaccinatedunvaccinatedvaccinatedunvaccinatedunvaccinatedvaccinatedvaccinatedvaccinatedunvaccinatedunvaccinatedunvaccinatedunvaccinatedvaccinatedunvaccinatedunvaccinatedunvaccinatedvaccinatedunvaccinatedvaccinatedvaccinatedvaccinatedvaccinatedunvaccinatedunvaccinatedvaccinatedvaccinatedvaccinatedvaccinatedseveremildsevereseveresevereseveresevereseveresevereseveresevereseveresevereseveremildsevereseveremildseveremildseveresevereseveremildmildseveresevereseveremildsevereseveresevere214041602140618080+4160618002021406180618061802140416021402140618021404160214080+416061804160618080+41604160618080+80+4160 3643653663673683693703713723733743753763773783793803813823833843853863873883893903913923933943952548406193517316256777693651332466244226944275518094424671949051unvaccinatedunvaccinatedunvaccinatedunvaccinatedvaccinatedunvaccinatedvaccinatedunvaccinatedunvaccinatedvaccinatedvaccinatedvaccinatedunvaccinatedunvaccinatedunvaccinatedunvaccinatedvaccinatedunvaccinatedunvaccinatedunvaccinatedvaccinatedunvaccinatedvaccinatedvaccinatedvaccinatedvaccinatedunvaccinatedunvaccinatedvaccinatedvaccinatedvaccinatedvaccinatedseveremildsevereseveresevereseveresevereseveresevereseveresevereseveresevereseveremildsevereseveremildseveremildseveresevereseveremildmildseveresevereseveremildsevereseveresevere214041602140618080+4160618002021406180618061802140416021402140618021404160214080+416061804160618080+41604160618080+80+4160