Parametric statistics is a branch of statistics which assumes that sample data comes from a population that can be adequately modelled by a probability distribution that has a fixed set of parameters.[1] Conversely a non-parametric model differs precisely in that the parameter set (or feature set in machine learning) is not fixed and can increase, or even decrease, if new relevant information is collected.[2] Most well-known statistical methods are parametric.[3] Regarding nonparametric (and semiparametric) models, Sir David Cox has said, "These typically involve fewer assumptions of structure and distributional form but usually contain strong assumptions about independencies".[4]

Statistical hypotheses concern the behavior of observable random variables.... For example, the hypothesis (a) that a normal distribution has a specified mean and variance is statistical; so is the hypothesis (b) that it has a given mean but unspecified variance; so is the hypothesis (c) that a distribution is of normal form with both mean and variance unspecified; finally, so is the hypothesis (d) that two unspecified continuous distributions are identical. It will have been noticed that in the examples (a) and (b) the distribution underlying the observations was taken to be of a certain form (the normal) and the hypothesis was concerned entirely with the value of one or both of its parameters. Such a hypothesis, for obvious reasons, is called parametric. Hypothesis (c) was of a different nature, as no parameter values are specified in the statement of the hypothesis; we might reasonably call such a hypothesis non-parametric. Hypothesis (d) is also non-parametric but, in addition, it does not even specify the underlying form of the distribution and may now be reasonably termed distribution-free. Notwithstanding these distinctions, the statistical literature now commonly applies the label "non-parametric" to test procedures that we have just termed "distribution-free", thereby losing a useful classification.

Non-parametric methods are widely used for studying populations that take on a ranked order (such as movie reviews receiving one to four stars). The use of non-parametric methods may be necessary when data have a ranking but no clear numerical interpretation, such as when assessing preferences. In terms of levels of measurement, non-parametric methods result in ordinal data. As non-parametric methods make fewer assumptions, their applicability is much wider than the corresponding parametric methods. In particular, they may be applied in situations where less is known about the application in question. Also, due to the reliance on fewer assumptions, non-parametric methods are more robust. Another justification for the use of non-parametric methods is simplicity. In certain cases, even when the use of parametric methods is justified, non-parametric methods may be easier to use. Due both to this simplicity and to their greater robustness, non-parametric methods are seen by some statisticians as leaving less room for improper use and misunderstanding. The wider applicability and increased robustness of non-parametric tests comes at a cost: in cases where a parametric test would be appropriate, non-parametric tests have less power. In other words, a larger sample size can be required to draw conclusions with the same degree of confidence.

The concept of data type is similar to the concept of level of measurement, but more specific: For example, count data require a different distribution (e.g. a Poisson distribution or binomial distribution) than non-negative real-valued data require, but both fall under the same level of measurement (a ratio scale).

Even if Muslims were hypothetically behind every single one of the 140,000 terror attacks committed worldwide since 1970, those terrorists would represent barely 0.009 percent of global Islam

That is, deaths from terrorism account for 0.025 of the total number of murders, or 2.5%

American Muslims have killed less than 0.0002 percent of those murdered in the USA during this period

How many people did toddlers kill in 2013? Five, all by accidentally shooting a gun

you actually have a better chance of being killed by a refrigerator falling on you

Since 9/11, Muslim-American terrorism has claimed 37 lives in the United States, out of more than 190,000 murders during this period

pproximately 60 were carried out by Muslims. In other words, approximately 2.5% of all terrorist attacks on US soil between 1970 and 2012 were carried out by Muslims.

94 percent of the terror attacks were committed by non-Muslims

Muslim terrorists were responsible for a meagre 0.3 percent of EU terrorism during those years.

in 2013, there were 152 terrorist attacks in Europe. Only two of them were “religiously motivated”, while 84 were predicated on ethno-nationalist or separatist beliefs

in the 4 years between 2011 and 2014 there were 746 terrorist attacks in Europe. Of these, only eight were religiously-inspired, which is 1% of the total

official data from Europol

info-request

info-request

要保持谦逊：兼容性评估的前提是用于计算区间的统计假设是正确的

在给定假设的情况下，区间内数值与研究数据的兼容性并不完全相同

我们看到了大量具有“统计学显著性”的结果；而不具有“统计学显著性”的结果则被显著低估

在置信区间包含风险显著增高的情况下，仅因为结果不具有统计学显著性就推论药物与房颤发生“无关”十分可笑；据此就认为前后两项研究矛盾——即便风险比完全一致——同样非常荒谬。这些常见情况表明我们依赖的统计学显著性阈值有可能误导我们。

At The Economist, we take data visualisation seriously. Every week we publish around 40 charts across print, the website and our apps. With every single one, we try our best to visualise the numbers accurately and in a way that best supports the story. But sometimes we get it wrong. We can do better in future if we learn from our mistakes — and other people may be able to learn from them, too.

the strongest first factor accounted for 86.3% of observed variable variance

The weakest first factor accounted for 18.3% of variance

The Doomsday argument

Basic Statistics

Online Options Give Adults Access, but Outcomes Lag

Double-centering a matrix M

Relationship between ridge regression and PCA regression

Lack of metrics

LDLC workers and their needs

predictive analysis

Boxplots and Beyond – Part II: Asymmetry

Using the Median Absolute Deviation to Find Outliers

Power analysis and sample size estimation for RNA-Seq differential expression

Polyester: simulating RNA-seq datasets with differential transcript expression

Combining data from multiple RNASeq experiments: release the Kruskal! (...Wallis test)

Neural correlates of interspecies perspective taking in the post-mortem Atlantic Salmon: an argument for multiple comparisons correction

The natural selection of bad science

HarvardX Biomedical Data Science Open Online Training

pairwise overlaps using Fisher’s test and mutual exclusion (Leiserson et al., 2016xA weighted exact test for mutually exclusive mutations in cancer. Leiserson, M.D.M., Reyna, M.A., and Raphael, B.J. Bioinformatics. 2016; 32: i736–i745Crossref | PubMed | Scopus (4)See all ReferencesLeiserson et al., 2016)

Gene Set Enrichment Analysis Made Simple

An Introduction to Odds, Odds Ratios and Exponents

One of the main ways computers are changing the textual humanities is by mediating new connections to social science. The statistical models that help sociologists understand social stratification and social change haven’t in the past contributed much to the humanities, because it’s been difficult to connect quantitative models to the richer, looser sort of evidence provided by written documents.

s. If we want to understand the effects of global warming or whether the economy is headed for a recessio

The annual drop in Maine wood demand since 2014 would fill that imaginary 1,770-mile caravan. The loss equals about 350 fewer truckloads of wood a day, every day of the year.

The state has pumped more than 100 million pounds of low bush fruit into the frozen market each year for the last three growing cycles.

A typical acre of blueberry barrens will yield about 2,000 to 4,000 pounds of berries, depending on pollination and other factors.

I never regret the eleven months which hardened my resolve, to go beyond 98 'Nos' to get to the precious, unexpected 'Yes's'. I was nobody, I was selling nothing, I could be nobody selling anything.

That two dice marked in the common way will tum up seven, is thrice as probable as that they will tum up eleven, and six times as probable as that they will tum up twelve

In moral reasoning we ascend from pos-~ibility, by an insensible gradation, to probabil-ity, and thence, in the same manner, to the sum-mit of moral certainty.

The course of nature will be the same tomorrow that it is today; or, the future will resemble the past"

With figures like those, it's clear that the education system isn't going away anytime soon.

According to the language periodical Språktidningen, ‘hen’ was by 2014 used once in the Swedish media for every 300 used of ‘hon’ or ‘han’, up from one in every 13,000 in 2011

the algorithm was somewhat more accurate than a coin flip

3,068 adults in August 2014, found that 72 percent of Americans reported feeling stressed about money at least some of the time during the past month. Twenty-two percent said that they experienced extreme stress about money during the past month (an 8, 9 or 10 on a 10-point scale, where 1 is “little or no stress” and 10 is “a great deal of stress”). For the majority of Americans (64 percent), money is a somewhat or very significant source of stress, but especially for parents and younger adults (77 percent of parents, 75 percent of millennials [18 to 35 years old] and 76 percent of Gen Xers [36 to 49 years old]).

He expects that the logging project near Quimby’s land will likely generate about $755,250 at the state’s average sale price, $50.35 per cord of wood. The land has about 1,500 harvestable acres that contain about 30 cords of wood per acre, or 45,000 cords, but only about a third of that will be cut because the land is environmentally sensitive, Denico said. The Bureau of Parks and Lands expects to generate about $6.6 million in revenue this year selling about 130,000 cords of wood from its lots, Denico said. Last year, the bureau generated about $7 million harvesting about 139,000 cords of wood. The Legislature allows the cutting of about 160,000 cords of wood on state land annually, although the LePage administration has sought to increase that amount.

The science of the individual relies on dynamic systems theory rather than group statistics. Its research methodology is characterized by “analyze, then aggregate” (analyze each subject separately, then combine individual patterns into collective understanding) rather than “aggregate, then analyze” (derive group statistics based on aggregate data, then use these statistics to evaluate and understand individuals).

P(B|E) = P(B) X P(E|B) / P(E), with P standing for probability, B for belief and E for evidence. P(B) is the probability that B is true, and P(E) is the probability that E is true. P(B|E) means the probability of B if E is true, and P(E|B) is the probability of E if B is true.

The probability that a belief is true given new evidence equals the probability that the belief is true regardless of that evidence times the probability that the evidence is true given that the belief is true divided by the probability that the evidence is true regardless of whether the belief is true. Got that?

Initial belief plus new evidence = new and improved belief.

This criterion is not based on any specific shape of the dose-response relationship.

In 1930 its population was 112,000. Today it is 36,000. The halcyon talk of “interracial living” is dead. The neighborhood is 92 percent black. Its homicide rate is 45 per 100,000—triple the rate of the city as a whole. The infant-mortality rate is 14 per 1,000—more than twice the national average.

What's really being measured is heterogeneity of opinion, not centrism.

analyses

The use of the term n − 1 is called Bessel's correction, and it is also used in sample covariance and the sample standard deviation (the square root of variance)

Sample variance can also be applied to the estimation of the variance of a continuous distribution from a sample of that distribution.

Suppose the value of for wages is 10% and the values of for kilograms of meat is 25%. This means that the wages of workers are consistent. Their wages are close to the overall average of their wages. But the families consume meat in quite different quantities. Some families use very small quantities of meat and some others use large quantities of meat. We say that there is greater variation in their consumption of meat. The observations about the quantity of meat are more dispersed or more variant.

n its space-time representation (Ogata, 1998), the ETASmodel is a temporal marked point process model, and a special case of marked Hawks process, withconditional intensity function(t;x;yjHt) =(x;y) +Xti<tk(mi)g(tti)f(xxi;yyijmi)

two cadavers

Hence the man who makes a good guess at truth is likely to make a good guess at probabilities