2021/7/12

Statistics 這個英文字不只是統計學?也是統計量!

談到統計學,對應的英文字自然是Statistics。如果你與我一樣,在讀英文的統計學時讀到Statistics這個字,可是從上下文看來,它指的不是學科、不是統計學這個領域,然後百思不得其解🙄

恭喜你發現英文世界的奧妙!😄 Statistics不只是統計學!

STATISTICS 也可以是統計量!

哇,這樣不是很容易搞混意思嗎?沒錯!所以看英文時要掌握文章脈絡(context,上下文),特別是單複數型態。

先從單數型態來看,statistic這個字是一個統計量(統計值),是可數的,因此它不只可以是一個,也可以是兩個、三個、多個,所以在複數型態時要加上s,因此,就變成了statistics,表示兩個以上的統計量!

所以,單數的statistic前面要加a表示一個,而文法上是單數型態,而statistics則數複數型態,例如:

A statistic is a random variable. (一個統計量是一個隨機變數)

Properties of statistics include completeness, consistency, sufficiency, ... (統計量的屬性包括了完備性、一致性、充分性...) (改自Wikipedia)

回到統計學的部分,就如同其他學科,後面接的字是第三人稱單數型態的be動詞或動詞(加s),例如:

Statistics is a science of analysis (統計學是分析的科學)
Statistics deals with data. (統計學處理著資料)

所以,statistic是只統計量,而statstics除了看上下文,只要清楚句子中的動詞,複數的話就是指好幾個統就量,單數的話通常是指統計學,如此一來,這兩種中文的意思就不難分辨囉!

最後稍微介紹一下統計量,由於統計量是用在統計而不是普查,因此不是直接用在母體(population),而是用在樣本。根據維基百科,統計量就是樣本統計量(sample statistic)

舉例來說,樣本平均數x̅,就是一個統計量。

關於統計量的更多介紹,未來有機會再整理,這個分享就先到這邊囉~

References:

Statistic (Wikipedia)

Basic Statistical Terms 統計學基本名詞 (StudyBME)

2021/3/11

Taxonomic rank 生物分類階元

小時候讀過「界門綱目科屬種」,是林奈體系(Linnaeu's System)的生物分類法(Taxonomic rank),對照英文,原來是這樣:

界 (Kingdom)
門(動物 Phylum/ 植物 Division)
綱(Class)
目(Order)
科(Family)
屬(Genus)
種(Species)

Biological classification L Pengo vflip      Biological classification L Pengo vflip zh


strain 分型 (Wikipedia)

References:

界門綱目科屬種的英文? (Yahoo知識+)

2020/9/21

R Programming Language - Run R Script

To run R script, install RStudio.

Add a new R script file and save it as a *.R file.


The code in the new script file can be:

a = 1

b = 2

a+b

When executing the script file, move the cursor to the first line of the script.

Press the run button, one line is run and the cursor is moved to the next line.

In the above example, press the run button three time for the three lines as below:



Related Information:

Installation and basic R commands

R programming language - load and save data

2020/9/3

R programming language - load and save data

This article explains the commands to load and save R data.

Firstly, declare data x:

    x = c(1,2,3,4,5,6)

Get the local path: getwd()

    path = getwd()

Change path:

    pathnew = file.path(path,"Desktop")

Set the local path: setwd()

    setwd(pathnew)

Save

    filename = file.path(pathnew,"test.RData")

    save(x,file=filename)

Clear workplace

    rm(list=ls())

Load

    filename = file.path(getwd(),"test.RData")

    load(filename)

    > x

    [1] 1 2 3 4 5 6

Related Information:

How to save and run an R Script

Installation and basic R commands

2020/8/18

Installation and Basic R commands

The R Project for Statistical Computing software is available with multiple operating systems such as Windows, MacOS.

It may be downloaded here:

https://www.r-project.org

After installation, try declare values with '=' or '<-' and see the average result with 'mean' function.

> x<-c(1,2,3,4,5)

> mean(x)

[1] 3

> y<-c(2,3,4,5,6,7,8)

> mean(y)

[1] 5

> z=c(5,6,7)

> mean(z)

[1] 6

Result:

To remove the above warning messages, open terminal and type:

defaults write org.R-project.R force.LANG en_US.UTF-8

Reference:

[記宅] 在 Mac 上安裝 R 語言 (R Studio, R) 新手介紹

Related Information:

R programming language - load and save data

How to save and run an R Script

2020/8/1

Hypothesis Testing 假設檢定名詞

hypothesis testing 假設檢定/假說檢定

null hypothesis 虛無假設 H0
alternative hypothesis 對立假設 H1/Ha

analysis ovariances (ANOVA) 變異數分析

E.g. 3 groups with one-way ANOVA
H0: μ1 = μ2 = μ3
H1: μ1 ≠ μ2 ≠ μ3

ANOVA的重點,是求F值:

F =MST/MSE = Mean Square Treatment/Mean Square Error

再和Critical Value CV=f(df1,df2)比較,CV可查f分佈表求得,當F值大於CV時,則拒絕H0

F值表示組間變異(variability between groups)較組內變異(variability within groups)多F倍,因此當F值越大,機率上組間的差異就越大,所以當F值增加至大於CV值時,組間有顯著異。

當F > CV時,組間有顯著差異,但不知道差異是在哪些組之間,因此需要事後檢定(post hoc test)

接著求p value,即在
可針對不同的α值查表求fα(df1,df2),例如f0.05(df1,df2)和f0.01(df1,df2)等數值,即可粗略地得知p值所落在的範圍


p value:
<0 ---="" .05="" br=""><0 ---="" .01="" br=""><0 ---="" .001="" br="">
<0 ---="" .05="" br=""><0 ---="" .01="" br=""><0 ---="" .001="" br="">p<0.05 ---  *     statistically significant
<0 ---="" .05="" br=""><0 ---="" .01="" br=""><0 ---="" .001="" br="">p<0.01 ---  **    statistically highly significant
<0 ---="" .05="" br=""><0 ---="" .01="" br=""><0 ---="" .001="" br="">p<0.001 --- *** statistically extremely significant
<0 ---="" .05="" br=""><0 ---="" .01="" br=""><0 ---="" .001="" br="">
test statistic 檢定統計量

significance level / level of significance 顯著水準 (通常α = 0.05)
- H0發生的機率、拒絕H0的機率、Type I error的機率(不太可能發生)

References

顯著水準 - 基礎統計名詞介紹網頁
Statistical significance (Wikipedia)
Foundations of ANOVA – Assumptions and Hypotheses for One-Way ANOVA (12-3) (Research By Design YouTube)
Mathematical statistics with applications in R, Ramachandran & Tsokos, 2nd edition (2015), p501,

Finding the P-value in One-Way ANOVA (YouTube)

p值的迷思:顯著與非常顯著 研究生2.0

2020/4/18

brain 腦

central nervous system (CNS) 中樞神經系統

cerebrum 大腦
cerebellum 小腦
brainstem/brain stem 腦幹
- midbrain 中腦
- pons 橋腦
- medulla oblongata 延腦

thalamus 視丘/丘腦


skull 頭顱/顱骨/頭骨/腦殼
scalp 頭皮
cortex 皮質

grey matter/gray matter 灰質
white matter 白質

cerebral cortex 大腦皮質

cerebral spinal fluid (CSF) 腦脊髓液

gyrus 回/腦回/腦迴
sulcus 溝
lobe 葉

frontal lobe 額葉
parietal 頂葉
occipital lobe 枕葉
temporal lobe 顳葉

central sulcus 中央溝


Cerebrum lobes.svg
By vectorized by Jkwchui - http://training.seer.cancer.gov/module_anatomy/unit5_3_nerve_org1_cns.htmlCC BY-SA 3.0Link

meninges 腦膜
meningeal veins 腦膜靜脈

1604 Types of Cortical Areas-02.jpg

Diagram from Wikipedia by OpenStax College - Anatomy & Physiology, Connexions Web site. http://cnx.org/content/col11496/1.6/, Jun 19, 2013., CC BY 3.0, Link


參考資訊

腦脊髓液(cerebral spinal fliud, CSF)
Specialized Instruments Brain Areas
Human Brain (Wikipedia)人腦(維基百科)
腦(小小整理網站)