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2015年7月29日星期三

校長的話

A message from the President and Vice-Chancellor on behalf of the Senior Management Team

Dear colleagues, students, alumni and friends,

We are all very concerned about the events that took place before, during and after the Council meeting yesterday on campus.

We cannot condone (容忍) the invasion of the Council chamber which prevented the Council from completing its rightful business. Council includes two elected student representatives and we implore (懇求) the students to express their concerns via these members so that discussions can take place in a calm and rational manner. The lack of respect for confidentiality which characterises HKU Council's discussions and decisions remains a serious concern for us.

We deplore (強烈譴責) violence by any party. We are still working to establish the facts about the various events on HKU campus last night and will not comment specifically on any follow-up actions until those facts are clear. As always, our primary concern is for the safety and security of all members of the University and of the general public: our Risk Assessment Team planned accordingly and we believe that HKU staff behaved professionally and reasonably throughout. It is regrettable that the police had to come onto campus, but ambulances were being barred from moving, which could have had serious consequences for the injured.

Prior to the Council meeting, outside parties were reportedly provoking (刺激的) HKU members and deliberately inciting (煽動) confrontations. Measures will be taken to ensure that the campus remains a safe place where routine academic activities can be conducted without harassment or intimidation (恐嚇).

The University will always respect and safeguard freedom of expression, but we must also strike a balance and do our best to guarantee the safety and well-being of all HKU members.

As we have repeatedly stated, all adults must take responsibility for their own actions.

Professor Peter Mathieson

President and Vice-Chancellor

梁智鴻醫生27/7的公開信

梁智鴻醫生致香港大學成員的公開信

各位港大成員:

        今天我以港大校友,以及港大校務委員會主席的身份與大家分享我對最近一些事件的看法。身為校友,我深深明白大家近來對委任副校長(學術人力資源)一事所表達的關心和焦慮,尤其當此事已引起大學成員以至大衆間廣泛的討論。我跟你們一樣,希望可以早日就事件作出決定,讓大學得以繼續邁步向前,致力成爲國際上首屈一指的大學。

        作爲校委會主席,我要一再重申,我所做的一切,皆以大學最佳利益為依歸。

        我想藉此機會向大家解釋下列幾點:

-         設立副校長(學術人力資源)一職的背景,其職能和職責
-         物色大學高層管理人員的既定程序
-         校委會在6月會議上的決定及其含義

背景

        副校長(學術人力資源)一職乃重設前副校長 (人力資源)五年多前離任後所懸空的職位。當時的校長認爲,設立了行政副校長一職後,可減輕首席副校長的工作, 因此或無需填補副校長(人力資源)一職。

        校委會屬下的人力資源政策委員會於2013 9月的會議,在審視大學管理層情況下,認爲需重設於同年6月會議中提出的「副校長」一職協助首席副校長,並提交文件建議其具體職務範圍需由首席副校長決定。

        校委會在20141月接納建議,並決定將該職位的職銜改為副校長 (學術人力資源),以「協助首席副校長處理學術事宜」。 (詳見2014128日的會議記錄)

物色大學高層管理人員的既定程序

        所有副校長皆透過以校長爲首、由校委會委任大學成員組成的物色委員會物色推薦。該委員會通常在獵頭公司協助下,開展全球性的物色工作。

        當物色委員會完成工作後,便會向作爲任命機構的校委會提交建議,而該建議可以是推薦一適合人選,有時甚至人選欠奉。

        校委會主席沒有參與物色委員會的任何工作。

校委會會議(2015630日)

        當我得知物色委員會擬於6月的校委會會議上提交建議時,我把該建議列入會議議程。按慣例,議程項目在會議舉行一星期前左右會以"嚴格保密"封發送給各校委會成員。基於保密理由,物色委員會的文件並沒隨封發送,而只供在會上閲覽。因此在會議前並沒透露任何有關物色委員會的報告内容。

        在會議舉行前幾天,有數名校委會成員要求我撤回議題或延後議決,直至大學已覓得新任首席副校長並能聽取其意見爲止。

        我並沒有從議程中刪除該議題。在會議中,有成員動議延後議決,得到和議。在徵求法律意見後,我同意討論「延後議決」這決議,接著我們就此進行深入的辯論、審議以及表決,最後作出「延後」的決定。因此,校委會暫時擱置審議物色委員會報告這項議程。

        值得一提的是,校委會在會議上從校長口中得知有機會最早於今年8月委任首席副校長一職。因此校委會是根據此情況並考慮副校長(學術人力資源)一職的具體職務範圍後,作出「延後議決」的決定。

        我想強調,校委會在討論、審議工作上均依從校委會規程行事,緊守集體決策和負責的原則。

延後的含意

        630日的決議並非如一些人士所想的:它不是解除該職位,亦不是摒棄物色委員會的推薦,而是把有關項目暫時擱置,以待徵求新任首席副校長的看法和意見。

        當校委會成員獲邀就事件投票時,我立即以主席的身份表明,在首席副校長人選落實後,便可徵求該候任人的看法和意見,而不須等待其正式上任。

有關2015728日校委會的決定

        6月份的校委會會議後,我與一行13名校友真誠交流,並收到其他校友及表達關注人士的信件及簽名。我決定在校委會報告其關注,並於7月份會議上加入一項相關的議程。在發出議程後,我收到一些校委會成員要求重新審議630日作出有關「延後」的決定。我已準備批准委員們重新審議有關決議,並會在明天舉行的校委會會議上提出討論。

本人的立場

        作為香港大學校友,我重申我非常希望大學可盡快向前邁進;然而作為校委會主席,我必須緊守管理校委會會議程序及決議的規則和規定。我將繼續竭盡所能,帶領作為大學受托人的校委會成員去審議事件,並作出對大學最有利的決定。我希望,亦相信,校委員成員定當同心協力,為大學謀福祉。

梁智鴻醫生

2015727

2015年7月18日星期六

df

Degrees of freedom refer to the number of observations in a sample that are "free to vary". Every observation increases degrees of freedom by one, but every coefficient the model estimates (including the constant) decreases the degrees of freedom by one.

Add a regression line

Graphs
     Chart Builder
          Gallery: Scatter/Dot
               Drag the Simple Scatter chart to the Chart preview
                Drag xxx from the variable list to the "X-axis" box
                Drag yyy from the variable list to the "Y-axis" box
     OK

double-click
Chart Editor

Elements
     Fit Line at Total

(multiple regression)
Options
     Reference Line from Equation
          Reference Line: Custom Equation: k + (bx)
          Apply
Close the Chart Editor

R square

The R-square statistic measures the regression model's usefulness in predicting outcomes --- indicating how much of the dependent variable's variation is due to its relationship with the independent variable(s).

Interpretation (p-value difference)

The coefficients will test the unique effect of each independent variables to the model, and the F-test will test the join effects of all the variables together.

B or slope

The unstandardized coefficient of an independent variable (also called B or slope) measures the strength of its relationship with the dependent variable. It is interpreted as the size of the average difference in the dependent variable that corresponds with a one-unit difference in the independent variable.

Linear regression

  1. In statistics, linear regression is an approach for modeling the relationship between a scalar dependent variable y and one or more explanatory variables (or independent variable) denoted X. The case of one explanatory variable is called simple linear regression.
  2. (source: google)
  3. Analyze
  4.      Regression
  5.           Linear
  6.                Dependent: xxx
  7.                Independent: yyy
  8.               OK

collective effects

One of the great benefits of regression analysis is its ability to document collective effects --- the interplay among factors on predicted outcomes...They also can measure the amount of variation in the dependent variable that can be attributed to the variables in the model, and conversely, how much of the variation is left unexplained.

2015年7月17日星期五

Typing exercise

明報 社評 筆陣
2015年7月17日

社評︰日本告別和平國家道路 中國應以實際行動反制

日本安倍政府強行在國會通過新安保法案,改變日本的和平國家道路;新法案是由專守防衛政策,一百八十度的變為可以對外用兵。以日本侵略往績和模糊史實、推卸戰爭責任的做法,現在竟然可以出兵他國,這個國家對本地區以至全球的和平構成什麼衝擊和影響,難以估計。日本首相安倍晉三不諱言新安保法案有助於應對包括中國崛起的挑戰,對於這般心態的日本,中國的溫良恭儉讓是不是已經過時?北京應該針鋒相對,並做好宿敵再次來犯的準備。

安倍逆民意強行通過

新安保法劍指中國

日本的新安保法案,除了學者紛紛表態指其違憲之外,主流民意也強烈反對。日本多家媒體的民意調查顯示,近六成日本民眾反對新安保法案,八成民眾認為國會審議草率,對法案無法理解。另外,安倍的民望顯著下滑,反對他任首相的比率已經超過支持度。不過,安倍背逆民意,堅持強推新安保法案,利用自民黨和公明黨執政聯盟在眾議院佔逾三分之二多數的優勢,強行通過法案。安倍對改變和平國家道路之志在必得,可說是不惜一切後果。

二戰之後70年,日本和平憲法被新安保法案徹底顛覆了;其憲法第9條規定日本實行「專守防衛」國策,可是新安保法案通過之後,即使日本沒有直接受到攻擊,仍然可以行使集體自衛權的名義而對其他國家動用武力。因此,安倍繞過修憲搞新安保法案,實際上使憲法第9條變得名存實亡。這意味著,日本可隨時根據需要向海外派兵並向其他國家軍隊提供支援,參與戰爭。對於有侵略往績、特別是美化侵略的日本,這個顛覆性的改變,使人不寒而慄。

日本和平憲法是由美國主導制定,日本一直想擺脫處處受掣肘的狀況,要成為一個「正常國家」。美國把戰略重心移向亞洲,搞所謂「亞太再平衡」,倚賴日本協作,共同遏制中國;美國此舉給予日本成為正常國家,提供了機會。新安保法案強行通過後,美國國務院第一時間表示歡迎,這絕非禮儀表態,而是新訂<<日美防衛指針>>,有關日本有義務在全球配合美軍軍事任務的規定,在法理上得以確立。

事實上,在審議新安保法案過程中,安倍一再表示法案目的包括應對中國崛起的挑戰,他針對中國的用心,或許較美國更強烈。安倍二度執政之後,對中國採取強硬立場,不斷宣揚所謂「中國威脅論」,又藉釣魚島事件渲染中日緊張關係,拉美國落水,然後在東海攪局,最新發展就是在南海事態也插上一腿。新安保法案可視為日本對中國構成戰略威懾,從安倍的角度,這是日本重振聲威、遏制中國的機會;就美日聯手,新安保法案可視為欲翻滾亞太局勢,遏制中國的立法。

安倍的用心,或許不止於此。6月底,有幾家日本周刊和網站接連爆出安倍一些驚人言論,事緣他與媒體高層在一個聯誼場合喝酒之後坦承︰「安保法案就是衝著南海上的中國」;媒體描述安倍「大大方方地承認自己確實在謀劃與中國的戰爭,並表示要行使集體自衛權,與美軍一起敲打在南海上的中國」云云。安倍這番話,日本官方並未釐清,僅含糊其辭,敷衍過去。酒後或許是胡言亂語,當不得真,卻同樣可以是酒後吐真言,講的是肺腑之言;據日本媒體描述,安倍當時喝了酒卻沒有喝醉,因此對這番酒後之言的理解,各人或許不同,但是可以肯定是絕非對中國友好的說辭。

不滿勿僅止於言辭

應有實際行動反制

就日本國會通過新安保法案,國務委員楊潔箎和外交部發言人都有回應,應該是反映了中國的立場,並對日本的做法提出警惕之意。然而,這些口頭說法,日本會在意嗎?且看新安保法案通過之際,日本國家安全保障局長谷內正太郎已抵達北京;據日方透露,他將與楊潔箎會面,討論安倍晉三能否在9月初訪華,並要與國家主席習近平舉行首腦會談,亦可能向中方說明安倍稍後發表的戰後70年談話方向,云云。

日本的外交工夫,做得十分細緻,通過針對中國的新安保法案的同時,谷內正太郎同時臨門,要商討首腦會談,客觀上陷入中國於難以推卻的景況。不過,這些都是小動作,若中國不滿安倍,仍然可以拒談什麼首腦會談。事實上,要習近平與謀劃對中國戰爭的安倍共商大計,是很大的諷刺。中國曾公開表示已經邀請安倍出席9月3日在北京舉行的紀念抗戰勝利的活動,日方則趁機操作為安倍到訪中國舉行首腦會談,這是日本企圖以四兩撥千斤,妄想在外交上化解壓力的盤算。問題是︰中國會否被日本牽著鼻子走?

在日本通過新安保法案之後,中國即時接待日本內閣官員,本來已經使人難以理解;在安倍就二戰70周年講話未知道將如何洗脫侵略罪行之前,中國與日方舉行首腦會談,顯然是褻瀆。日本咄咄逼人,中國目前的取態應該是適度地強硬,對日本開展針鋒相對的鬥爭,而非讓日本在外交上予取予攜。嚴格而言,現在北京對日關係降級甚至召回大使,都是可以考慮的選項。

http://www.bbc.com/news/world-asia-33549015

Japan's (self) defence forces
16 July 2015

The impassioned debate surrounding Prime Minister Shinzo Abe's desire to give Japan's defence forces a wider role obscures the fact that the country is already a significant military player. It has well-equipped air, sea and land forces with ambitious modernisation plans under way.

The defeat of Japanese militarism in World War Two and the experience of suffering the world's only atomic bomb attacks left the country with a deep vein of pacifism.

But Japan's strategic geography - proximity to both the then-Soviet Union and China - meant that it ultimately needed to deploy its own basic defence forces. Their role though was heavily circumscribed and Japan avoided all foreign military entanglements.

Some 70 years later, the picture has changed dramatically. The Cold War may be over and the Soviet Union no more but now a rising China is driving security concerns in the region.

Japan remains the United States' key ally in the region. And with the scale and reach of China's military growing significantly, Japan has been modernising its own forces.

Chinese driver

Its army of some 150.000 troops is small (but still larger than that of Britain, one of Nato's middle-ranking players whose forces stand at some 84,000).

It has an impressive navy including a small helicopter carrier, two Aegis-equipped cruisers with sophisticated radars and battle management systems, and some 34 destroyers and nine frigates of various types. It also has some 80 anti-submarine warfare or maritime patrol aircraft.

Given the potential threat from North Korea's missile arsenal, Japan has a growing interest in ballistic missile defence.

The country hosts two highly sophisticated US radars to track such weapons. It currently has four destroyers capable of shooting down ballistic missiles along with land-based PAC-3 missile interceptors. More are planned.

But above all it is China's widening security horizons that are driving Japan's military modernisation.

This year, Japan's Maritime Self-Defence Force commissioned its largest vessel yet - a new helicopter carrier - the JS Izumo. This could potentially embark a number of V- 22 Osprey vertical lift aircraft - and Japan is thought to be interested in buying up to 17 of them from the United States.

More Aegis anti-missile warships are planned and brand new, Japanese-built maritime patrol aircraft are coming into service.

Foreign exercises

Over the years, Japan has also widened its sphere of international military activities.It's been a slow process with the country dipping its toes slowly into the field of foreign entanglements.

But Japanese warships have participated in international anti-piracy operations off the Horn of Africa and Japanese maritime patrol aircraft have supported this mission from Djibouti.

Japan has also slowly begun to take part in military exercises further from its shores. In July 2014, it participated for the third time in joint US-indian naval manoeuvres and a small contingent of Japanese troops is currently involved in the joint US-Australian Talisman sabre exercise.

So in many ways the sorts of reforms being pushed by Prime Minister Abe have already been under way - little by little - for many years.

Nonetheless, making the changes explicit raises strong passions among the Japanese public, and any perceived revival of Japan as a military player prompts strong reactions from those who have suffered from its military expansionism in the past - notably China.

What is collective self-defence?

Japan's post-World War Two constitution bars it from using force to resolve conflicts except in cases of self-defence.

Mr Abe's government has pushed for a change that would revise the laws such that Japan's military would be able to mobilise overseas when these three conditions are met


  • when Japan is attacked, or when a close ally is attacked, and the result threatens Japan's survival and poses a clear danger to people
  • when there is no other appropriate means available to repel the attack and ensure Japan's survival and protect its people
  • use of force is restricted to a necessary minimum
Some strategists might say that the military distinction between self-defence and a more expansive regional military role is redundant.

In the maritime sector, defence must be forward - beginning far from a country's own shores. Japan's defence depends fundamentally upon its close alliance with the United States and thus it makes sense for Japan's armed forces to operate according to similar concepts and strategic parameters.

This though is to overlook the huge weight of history in the region - a burden made even heavier by suspicions among some countries that Japan has not really fully come to terms with its aggressive past.

Whatever the statements of some more conservative Japanese politicians, the anguished debate over the country's changing posture would suggest that many ordinary Japanese are all too well aware of their history which makes Mr Abe's path a bumpy one to say the least.

2015年7月12日星期日

paired-samples t test

Analyze
     Compare means
          Paired-Samples T test
               Paired Variables: xxx
                                            yyy
               OK

t value and sig.(2 tailed)

A t value close to 0 indicates that the two means are very similar and will result in a large significance value.

T tests

A t test is a special case of analysis of variance that compares the means of only two categories. There are two types --- an independent samples t test and a paired samples t test.

Equal variance assumption

A rule of thumb is that the ratio of the largest variance to the smallest group variance should be no larger than 9.

Simple Maths

The average of the squared differences from the Mean.
Standard deviation is the square root of the Variance.

http://www.mathsisfun.com/data/standard-deviation.html

Histogram (normality assumption)

Graphs
     Chart Builder
          Gallery: Histogram
                Drag Simple Histogram to the Chart Preview
           Groups/Point ID: Columns Panel Variable
           Element Properties: Display normal curve
                Apply
            Drag xxx from "Variables" list to "X-axis?" box
            Drag yyy from "Variables" list to "Panel" box
            OK

Assumptions of ANOVA

ANOVA assumes the samples are independent, and each group's distribution is normal with the same standard deviation.

Post-hoc Tests

  1. Because post hoc tests are run to confirm where the differences occurred between groups, they should only be run when you have a shown an overall significant difference in group means (i.e., a significant one-way ANOVA result).
  2. (source: google)
  3. Analyze
         Compare Means
              One-way ANOVA
                   Dependent List: xxx
                   Factor: yyy
                   Options
                        Statistics: Descriptive
                        Continue
  4.                Post-hoc: Equal Variances Assumed: Tukey
  5.                     Continue
  6.                OK

One-way analysis of variance

Analyze
     Compare Means
          One-way ANOVA
               Dependent List: xxx
               Factor: yyy
               Options
                    Statistics: Descriptive
                    Continue
               OK

2015年7月11日星期六

Point ID added

Graphs
     Chart Builder
          Gallery: Scatter/Dot
               Drag the Simple Scatter chart to the Chart preview
                Drag xxx from the variable list to the "X-axis" box
                Drag yyy from the variable list to the "Y-axis" box
          Groups/Point ID: check Point ID label
               Drag zzz from the Variables list to the new Point ID box in the Chart Preview
           OK

Scatterplots by SPSS

In these graphs, the independent variable is usually placed on X axis and the dependent variable is placed on the Y axis.

Graphs
     Chart Builder
          Gallery: Scatter/Dot
               Drag the Simple Scatter chart to the Chart preview
                Drag xxx from the variable list to the "X-axis" box
                Drag yyy from the variable list to the "Y-axis" box
     OK

concept of correlation

A correlation does not mean that one variable causes the change in the other variable to occur, only that their values are associated.

Sigma notation

http://mathlesstraveled.com/appendices/sigma-notation/

Pearson's correlation coefficient

Analyze
     Correlate
          Bivariate:
               Variables: xxx
                                 yyy
               Correlation Coefficients: Pearson
                Tests of Significance: Two Tailed
                OK

example of inverted U-shaped relationship (correlations)

Relationship between test anxiety and test performance is an inverted U.
People whose anxiety is very low (mentally sleepy) or very high (overwrought with anxiety) perform worse than those whose anxiety is moderate (alert and sharp).

Stacked bar chart for bivariate analysis (2 categorical variables)

Graphs
     Chart Builder
          Gallery: Bar
               Drag the stacked bar chart up to the Chart preview
               Drag xxx from the Variable list to the "X-Axis" box
               Drag yyy from the Variable list to the "Stack: set color" box
     Elements Properties dialog
          Statistics: Percentage ()
          Set Parameters
               Total for Each X-Axis Category
          Continue
          Apply
     OK

Chi-square test for two categorical variables

Chi-square test = sum of relative differences between the observed and expected frequencies

Analyze
     Descriptive Statistics
          Crosstabs
               Rows: xxx
               Columns: xxx
               Cells
                    Counts: Observed
                    Percentages: Column
                    Continue
               Statistics
                    Chi-square
                     Continue
               OK

percentages added

Analyze
     Descriptive Statistics
          Crosstabs
               Rows: xxx
               Columns: xxx
               Cells
                    Counts: Observed
                    Percentages: Column
                    Continue
               OK

Cross tabulations

Analyze
     Descriptive Statistics
          Crosstabs
               Rows: xxx
               Columns: xxx
               OK

significance level

  1. The null hypothesis is rejected if the p-value is less than the significance or α level. The α level is the probability of rejecting the null hypothesis given that it is true (type I error) and is most often set at 0.05 (5%).
  2. (source:google)

Bivariate analysis

Cross tabulations measure the association between two categorical variables (such as ethnicity and religion).

Correlations measure the association between two scale variables (such as income and age).

2015年7月6日星期一

Basic Excel command

SUMIF
SUMIF(range, criteria, [sum_range])
https://support.office.com/en-ca/article/SUMIF-function-169b8c99-c05c-4483-a712-1697a653039b

Others:
http://www.excelfunctions.net/Basic-Excel.html
http://www.gcflearnfree.org/excel2010/10

2015年7月5日星期日

Alpha Coefficient

The Alpha score can range between 0 and 1, with higher numbers indicating higher reliability. As a rule of thumb, an Alpha score of .70 or higher on an index of four or more indicators indicates reasonably good reliability.

Analyze
     Scale
          Reliability Analysis
               Items = XXX
                             YYY
                             ...
               OK

MEAN.3

It designates that the average is based on three or more valid responses (6 questions)

note within syntax file

To insert a note within an SPSS syntax file, use the asterisk (*) character at the beginning and end of the note and separate the note with at least one blank line from the next command within the syntax file.

syntax files instead of the dialog windows

First, syntax files keep records of how variables were computed and how analyses were performed. Consequently, a researcher can perform extensive analyses and use the syntax files to track data manipulations through the course of the project.

Second, syntax files perform repetitious tasks quickly. For example, you can block, move, and copy portions of syntax files just as in word processing programs.

Index

An index is a single score that summarizes responses to two or more variables.

Syntax files

Syntax files contain procedures written in the SPSS command language that, when submitted, cause the SPSS processor or perform statistical operations. Syntax files are an alternative, as well as a supplement, to the dialog windows.

2015年7月4日星期六

Compute Variable

Transform
     Compute Variable...
          Target Variable = XXX
          Numeric Expression = "equation"
          Type & Label
               Label: XXX
               Continue
          OK

Swaying the result

Transform
     Recode Into Different Variables
          Numeric Variable: CRC86
          Output Variable Name: EXECUTE2
          Output Variable Label: Number of Executions 1930 to 2008, Texas Recoded Missing
          Change
          Old and New Values
               Old Value: Range, value HIGHEST: 0
               New Value: Copy old values
               Old Value: System- or User-missing
                    Continue
               OK
Transform
     Recode Into Same Variables
          Variables: EXECUTE2
     IF...
          Include if case satisfies condition:
               STATEID=44
          Continue
    Old and New Values
         Old Values: Range, value through HIGHEST: 0
         New Value: System-missing
    Add
    Continue
OK

Compare data

Analyze
     Reports
          Case Summaries
               Variables: XXX
                                 YYY
                OK

Constructing Variables 1

Transform
     Recode Into Different Variables
          Numeric Variable: XXX
          Output Variable Name: XXX
          Output Variable Label: XXX
               Change

(e.g. State Had One or More Executions 1930 to 2008)
Old and New Values
     Old Value: 0
     New Value: 0
     Add

     Old Value: Range, value through HIGHEST: 1
     New Value: Value: 1
     Add

     Old Value: System- or user-Missing
     New Value: System-missing
     Continue
OK

Transform...Recode Into Different Variables

SPSS offers two choices under the recode command: Into Same Variable and Into Different Variables. The command Into Same Variable replaces existing data with new values, but the command Into Different Variables adds a new variable to the data set. In almost every situation, we suggest selecting Into Different Variables. Because recoding Into Same Variables replaces the values in the existing variable, it will irrevocably alter a data set, threatening your access to the original data. For these reasons, it is best to not recode over an an existing variable unless you are absolutely confident that the lost information will never be needed.

2015年7月1日星期三

Beetle likes The Beatles


Illustrating a list

Analyze
     Reports
          Case Summaries
               Variables: XXX
                                 XXX

Demonstrating histogram

Graphs
     Chart Builder
          Gallery: Histogram
               Drag the first histogram to the Chart preview.
               Drag XXX from the Variable list to the "X-axis" box.
          Element Properties
               Check Display Normal Curve
          OK

Demonstrating Box Plot Diagram

Analyze
     Descriptive Statistics
          Explore
               Display: Both
               Dependent List: XXX
               OK

Showing median

Analyze
     Descriptive Statistics
          Explore
               Dependent List: XXX
                    OK

Showing mean

Analyze
     Descriptive Statistics
          Descriptives
               Variable: XXX
                    OK

Bimodal distribution

It is also symmetric, but the highest frequencies are at both ends, with few cases in the middle. Daytime traffic accidents fit this pattern, with most accidents occurring in the early mornings and late afternoons during the commute to and from work.

Chart Editor

To access the Chart Editor, double click on the histogram in the Output window. This opens the SPSS Chart Editor window. You will observe new options next to the graph, which allow you to change titles, axis labels, axis scales, etc.

Histograms

A histogram is a graphic summary of the distribution of a scale variable. In a histogram, classes of values are listed along the horizontal axis. The height of the bar above each class indicates the number of cases with values in that class.