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Presentation given last year at UFRJ about the dangers of misused statistics in biology. Beware of the dynamite (graphs)!
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Playingdumb:themisuse of
Statistics inBiology
Luiz Max F.de CarvalhoProgram for
ScientificComputing(PROCC),
Fiocruz
Preliminaries
Braindeadgraphs
Statistics hasconfirmed it.What!?
What should Ido then?
Playing dumb:the misuse of Statistics inBiology
Luiz Max F. de CarvalhoProgram for Scientific Computing (PROCC), Fiocruz
November 26, 2012
Playingdumb:themisuse of
Statistics inBiology
Luiz Max F.de CarvalhoProgram for
ScientificComputing(PROCC),
Fiocruz
Preliminaries
Braindeadgraphs
Statistics hasconfirmed it.What!?
What should Ido then?
Outline
1 Preliminaries
2 Braindead graphs
3 Statistics has confirmed it. What!?
4 What should I do then?
Playingdumb:themisuse of
Statistics inBiology
Luiz Max F.de CarvalhoProgram for
ScientificComputing(PROCC),
Fiocruz
Preliminaries
Braindeadgraphs
Statistics hasconfirmed it.What!?
What should Ido then?
Statistics – seems like but – is not magic!
In its origins, created to make sense of incompletedata/information;
A useful, powerful and flexible way of coping withuncertainty;
Widespread (mis)use in modern science
Playingdumb:themisuse of
Statistics inBiology
Luiz Max F.de CarvalhoProgram for
ScientificComputing(PROCC),
Fiocruz
Preliminaries
Braindeadgraphs
Statistics hasconfirmed it.What!?
What should Ido then?
Braindead graphs I - Why the heck 3D?
Playingdumb:themisuse of
Statistics inBiology
Luiz Max F.de CarvalhoProgram for
ScientificComputing(PROCC),
Fiocruz
Preliminaries
Braindeadgraphs
Statistics hasconfirmed it.What!?
What should Ido then?
Braindead graphs II - stick with 2D
Playingdumb:themisuse of
Statistics inBiology
Luiz Max F.de CarvalhoProgram for
ScientificComputing(PROCC),
Fiocruz
Preliminaries
Braindeadgraphs
Statistics hasconfirmed it.What!?
What should Ido then?
Spreads matter
Playingdumb:themisuse of
Statistics inBiology
Luiz Max F.de CarvalhoProgram for
ScientificComputing(PROCC),
Fiocruz
Preliminaries
Braindeadgraphs
Statistics hasconfirmed it.What!?
What should Ido then?
Dynamite is a bomb!
Don’t show data variation;
Who said means mean anything?
Where are the data?
Playingdumb:themisuse of
Statistics inBiology
Luiz Max F.de CarvalhoProgram for
ScientificComputing(PROCC),
Fiocruz
Preliminaries
Braindeadgraphs
Statistics hasconfirmed it.What!?
What should Ido then?
Dynamite is a bomb!
Playingdumb:themisuse of
Statistics inBiology
Luiz Max F.de CarvalhoProgram for
ScientificComputing(PROCC),
Fiocruz
Preliminaries
Braindeadgraphs
Statistics hasconfirmed it.What!?
What should Ido then?
I took the mean of an intervalar scale! Oh, please...
Beverage Average Rank
Coca-Cola 1.6Pepsi 3.3
Dr. Pepper 4.47up 4.9
Ginger ale 5.2
Playingdumb:themisuse of
Statistics inBiology
Luiz Max F.de CarvalhoProgram for
ScientificComputing(PROCC),
Fiocruz
Preliminaries
Braindeadgraphs
Statistics hasconfirmed it.What!?
What should Ido then?
Oh, so tiny!
Playingdumb:themisuse of
Statistics inBiology
Luiz Max F.de CarvalhoProgram for
ScientificComputing(PROCC),
Fiocruz
Preliminaries
Braindeadgraphs
Statistics hasconfirmed it.What!?
What should Ido then?
Oh, so tiny?
Asymptotic normality;
Power;
Multiple testing
Playingdumb:themisuse of
Statistics inBiology
Luiz Max F.de CarvalhoProgram for
ScientificComputing(PROCC),
Fiocruz
Preliminaries
Braindeadgraphs
Statistics hasconfirmed it.What!?
What should Ido then?
There’s a linear relationship. What!?
Playingdumb:themisuse of
Statistics inBiology
Luiz Max F.de CarvalhoProgram for
ScientificComputing(PROCC),
Fiocruz
Preliminaries
Braindeadgraphs
Statistics hasconfirmed it.What!?
What should Ido then?
There’s a linear relationship. What!?
OLS assumes normality and homokedasticity
You only need two points to make a straight line
Residuals analysis is as much important as everything else
Playingdumb:themisuse of
Statistics inBiology
Luiz Max F.de CarvalhoProgram for
ScientificComputing(PROCC),
Fiocruz
Preliminaries
Braindeadgraphs
Statistics hasconfirmed it.What!?
What should Ido then?
What should I do then?
Try and show the data;
Avoid unecessary multiple testing
Non-parametrics and Bayesian alternatives
Power Calculations
Playingdumb:themisuse of
Statistics inBiology
Luiz Max F.de CarvalhoProgram for
ScientificComputing(PROCC),
Fiocruz
Preliminaries
Braindeadgraphs
Statistics hasconfirmed it.What!?
What should Ido then?
Tanquiu iu veri mati!
