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<blockquote> | <blockquote> | ||
#P-values can indicate how incompatible the data are with a specified statistical model. | #P-values can indicate how incompatible the data are with a specified statistical model. | ||
# P-values do not measure the probability that the studied hypothesis is true, or the | # P-values do not measure the probability that the studied hypothesis is true, or the probability that the data were produced by random chance alone. | ||
probability that the data were produced by random chance alone. | # Scientific conclusions and business or policy decisions should not be based only onwhether a p-value passes a specific threshold. | ||
# Scientific conclusions and business or policy decisions should not be based only | |||
#Proper inference requires full reporting and transparency. | #Proper inference requires full reporting and transparency. | ||
# A p-value, or statistical significance, does not measure the size of an effect or the | # A p-value, or statistical significance, does not measure the size of an effect or the importance of a result. | ||
importance of a result. | #By itself, a p-value does not provide a good measure of evidence regarding a model or hypothesis. | ||
#By itself, a p-value does not provide a good measure of evidence regarding a model or | |||
hypothesis. | |||
</blockquote> | </blockquote> | ||
The FiveThirtyEight blog developed an interactive demonstration of p-value hacking, entitled [http://fivethirtyeight.com/features/science-isnt-broken/?ex_cid=endlink#part2 Hack Your Way To Scientific Glory]. A scatterplot shows the strength of the economy vs. the degree of political power of your preferred party (choose Democrat or Republican). Your mission is to show that having your party "in control" of the government helps "the economy" by tweaking how the variables are defined. | The FiveThirtyEight blog developed an interactive demonstration of p-value hacking, entitled [http://fivethirtyeight.com/features/science-isnt-broken/?ex_cid=endlink#part2 Hack Your Way To Scientific Glory]. A scatterplot shows the strength of the economy vs. the degree of political power of your preferred party (choose Democrat or Republican). Your mission is to show that having your party "in control" of the government helps "the economy" by tweaking how the variables are defined. | ||
==Item 2== | ==Item 2== | ||
Revision as of 18:13, 15 July 2016
Quotations
Forsooth
"There are 33 percent more such women in their 20s than men. To help us see what a big difference 33 percent is, Birger invites us to imagine a late-night dorm room hangout that’s drawing to an end, and everyone wants to hook up. 'Now imagine,' he writes, that in this dorm room, 'there are three women and two men.'"
Cited in Imagine 33 percent at Jordan Ellenberg's "Quodmodocumque" blog (20 November 2015).
Submitted by Priscilla Bremser
“I showed all the data together, which helped disguise the bimodal distribution. Nothing wrong with that. All the data is there. Every piece.... [But then he suggested using] thick and thin lines to try and dress it up, or changing colors to divert attention.”
quoted in: Takata emails show brash exchanges about data tampering, New York Times, 4 January 2016
Submitted by Bill Peterson
p-values
The ASA's statement on p-values: Context, process, and purpose
by Ronald L. Wasserstein and Nicole A. Lazar, The American Statistician, 70:2 (2016).
Quoting from the report, here are six principles:
- P-values can indicate how incompatible the data are with a specified statistical model.
- P-values do not measure the probability that the studied hypothesis is true, or the probability that the data were produced by random chance alone.
- Scientific conclusions and business or policy decisions should not be based only onwhether a p-value passes a specific threshold.
- Proper inference requires full reporting and transparency.
- A p-value, or statistical significance, does not measure the size of an effect or the importance of a result.
- By itself, a p-value does not provide a good measure of evidence regarding a model or hypothesis.
The FiveThirtyEight blog developed an interactive demonstration of p-value hacking, entitled Hack Your Way To Scientific Glory. A scatterplot shows the strength of the economy vs. the degree of political power of your preferred party (choose Democrat or Republican). Your mission is to show that having your party "in control" of the government helps "the economy" by tweaking how the variables are defined.