Friday, December 31, 2004

Have you made a donation...

... for the south Asia earthquake/tsunami catastrophe?

Wednesday, December 29, 2004

The new math syllabus (3)

So, let's look at what's disappeared from the new math curriculum:

1. Differential equations. This is expected, and reasonable, since AFAIK no university curriculum assumes knowledge of applied maths and this has to be taught again anyway. (Except that I remember when I took a course in solid-state physics in year 1, students were supposed to solve PDEs when they didn't even know what an ODE is...)

2. Complex numbers. This is widely considered to be a difficult topic and is often given up altogther, but should we really just let students go away without knowing that a square root can be taken off from -1? So they know pi, e, but not i... and hence will not know e^{i pi} = ??

3. Harder coordinate geometry including conic sections (parabola, ellipse and hyperbola) and 3-D lines and planes.

4. Numerical methods. Even the "method of bisection" in maths seem disappeared. The stuff about Newton's method etc. get removed reasonably, I think. But strangely enough they teach trapezoidal rule.

5. The majority of the rest of Pure Maths. This includes, for a few examples,
i. logic (which I complained here before)
ii. arithmetic-geometric inequality and Cauchy-Schwarz inequality
iii. limits, covergence of sequences, L'Hospital's rule, Taylor expansion, etc.

The deletion of the majority of pure maths is inevitable, but still I'm not quite happy with this. The most important thing is not about a particular topic not being covered, but that students do not get a chance to see what mathematics really is, without the exposure to the complexity of "pure" maths.

I like pure maths.

Monday, December 27, 2004

merry christmas, spam filter

It seems that our departmental spam filter is enjoying his christmas holiday, and refuse to classify the majority of spams and let them remain in the inbox.

Saturday, December 25, 2004

noise complaint

It is not a very interesting event in the Christmas day, particularly since it happens at 9 am: someone living in the flat exactly below me come up and complain that we generate "noise" in these recent 10+ days at midnight, "opening drawers, closing doors and windows loudly", etc.
This is simply impossible for this to be true, especially when the other people living with him do not seem to hear the same thing. Given that he complains every several months, and claims that each time after he complains the problem goes away for a while, it seems that his hearing problem is quite periodic...

Monday, December 20, 2004

First day in ISAAC

We go to ISAAC at UST today. As in any other conference, my mind is doing everything but listening to the talks.

What's not so good about this conference is that student registration does not include the proceedings. OK, I know, local students do not need to pay, but I remember back in SoCG'2000, local student registration was also free but did include a copy of the proceedings...

With no proceedings at hand I don't know which session to attend; just looking at the topic is often not enough. This is particularly true when they arrange 4 talks in a "game theory" session when only one talk is about game theory. And tomorrow there will be a game theory talk that gets arranged into a session on "complexity"...

Sunday, December 19, 2004

7 seconds on ebay

I never have luck bidding on ebay (actually I never successfully bid anything there). And although I heard about this long before, this only occurs to me for the first time - that I'm outbid only 7 seconds before the deadline. Interestingly, there are actually two people who outbid me, and they differ in only 1 second.

Friday, December 17, 2004

The new math syllabus (2)

The new math curriculum is divided into a compulsory part and two elective parts. The two elective parts are more-or-less applied/statistics stream and pure math stream, respectively. And, you are not allowed to take both elective parts. So learning mathematical induction forbids you from learning statistics. While not very satisfactory to me, it is still understandable - after all, you cannot teach that much in three years, and the weaker students will never understand anyway.

Compulsory part

Basically it covers most of the materials in the old math syllabus, which is expected. What looks more interesting is its coverage of:
- set notations
- conditional probability
- permutations and combinations
All these are also taught in our discrete math class. So we do not need to teach these anymore, huh?

Elective I

This is a very "applied maths/M&S" thing with some simple calculus (involving only polynomials), but at least it talks about "e" and the natural logarithm. They seem to think that probability/statistics is very important: it includes Bayes theorem; binomial, Poisson and normal distributions; hypothesis testing, etc. Basically everything about statistics in AppliedMath.

Elective II

It is mostly AMaths/PureMaths. Talks about calculus to a greater depth, mostly at AMaths level, except including integration by parts and natural logarithms. Vectors and matrices seems being covered to the Applied/Pure level. It also covers trapezoidal rule (not quite expected), MI and binomial theorem etc.

Perhaps it is more interesting to see what is not covered... which I'll say next time...

Thursday, December 16, 2004



Thursday, December 09, 2004

紅灣 IPO

決 定 把 紅 灣 半 島 拆 卸 重 建 的 地 產 發 展 商 新 創 建 主 席 鄭 家 純 先 生 昨 天 說 , 紅 灣 半 灣 的 外 觀 「 唔 係 咁 好 睇 」 , 把 它 拆 掉 重 建 可 以 令 維 港 海 岸 更 美 觀 , 不 會 出 現 難 看 的 建 築 群 ; . . . 事 實 上 維 港 兩 岸 的 建 築 物 不 管 是 住 宅 樓 宇 或 商 業 樓 宇 都 乏 善 足 陳 , 真 正 美 觀 的 可 說 寥 寥 可 數 , 更 多 的 是 外 貌 平 庸 、 毫 無 特 色 的 玻 璃 幕 牆 大 廈 , 即 使 全 港 最 高 的 國 際 金 融 中 心 二 期 也 不 見 得 如 何 美 觀 , 有 不 少 人 就 批 評 它 的 高 度 破 壞 了 香 港 島 的 山 巒 景 色 。 若 果 按 照 鄭 先 生 的 邏 輯 , 那 不 但 紅 灣 半 島 該 拆 , 大 部 份 維 港 兩 岸 的 建 築 物 包 括 國 金 二 期 都 該 拆 卸 重 建 , 只 有 這 樣 才 能 令 維 港 兩 岸 面 貌 煥 然 一 新 , 鄭 先 生 下 一 步 是 不 是 準 備 購 入 其 他 維 港 兩 岸 樓 宇 拆 卸 重 建 呢 ?

係啦,我想炸晒 gor D 樓好耐啦...

其實想拆左佢好易,只要將個項目注入一間新公司,公開招股上市,市民爭相認購,如有任何人敢反對拆樓,實俾人指住閙: "你唔好阻住我發達!"

Wednesday, December 08, 2004

The new Math syllabus

So, we are going to have yet another education reform at secondary schools. I'm interested to see how they combine Maths, Additional Maths, Pure Maths, Applied Maths and M&S into a single subject. Having been hired for producing high-school math materials for several years, and being a math enthusiast, I think I could say something about it - probably over several coming blog entries.

Saturday, December 04, 2004


If you don't know what "astronaut" mean, you are qualified as an HK university student.

Tonight a TV programme talks about kindergarten kids learning words such as "astronaut" and "slithering". It is certainly too difficult for kids as young as that. But then they go to HKU campus, and found out that an average HKU student don't know the word "astronaut"...

Maybe I'm expecting too much. There are discrete math students who don't know what "multiple of 3" is. Perhaps we'll need a quiz paper in Chinese next year.

Friday, December 03, 2004


Today, a group of talented undergrad and postgrads chat about bad things in university (CS in particular) education. This includes: things are not taught in the correct courses but appear in other courses; there's not enough theory; there should not be too practical things like MCSE; things are simply not taught at all; learnt nothing from courses except blowing water; MSc being completely money-oriented; university education is not vocational training; we didn't catch plagiarism enough; students' plagiarism skills are too bad; students don't even bother to hide evidences of plagiarism; etc. etc.

I didn't speak up. After years, I don't have the "fire", although I still remember I like to catch plagiarism years ago. Things are not going to change no matter how much you dislike it. University students are customers, and we all know what they want.

Tuesday, November 30, 2004

唔 住 得 人

新 世 界 執 行 董 事 梁 志 堅 昨 批 評 , 紅 灣 半 島 的 質 素 遠 差 於 私 人 樓 宇 , 「D 廁 所 大 肚 婆 都 入 唔 到 去 , 連 好 似 我 咁 一 般 身 形 人 都 入 唔 到 , 企 埋 一 邊 都 閂 唔 到 門 , 入 到 去 重 撞 到 個 洗 手 盆 。 」

房 屋 政 策 評 議 會 總 幹 事 葉 肖 萍 稱 , 當 年 新 世 界 亦 有 份 興 建 紅 灣 , 昨 日 的 言 論 是 「 自 打 嘴 巴 」 。 地 球 之 友 環 境 事 務 經 理 朱 漢 強 更 質 疑 , 新 世 界 作 為 參 建 商 , 「 點 解 會 起 一 D 唔 住 得 人 ge 地 方 畀 人 住 ? 」

Monday, November 29, 2004


Some days ago I have lunch with someone. He told me that, contrary to the perhaps commonly perceived image, law students are extremely weak in logic. According to him (who worked as an IT staff in a university law department), those students simply can't think anything in a logical way. He wonders how these people can go out and "debate" in court.

I think this is not only true in law but also in many different fields. Does the department really require a potential student to have logical thinking? (Require them to have an A in Pure Maths?) Handling divorce and things likethat does not require any logical thinking.

This lead to something that I've been wondering for long, and that is, why we couldn't teach logic earlier in high school - not just in Pure Maths, but in lower levels so that everyone, even those in the arts stream, know some logic. People find difficulty in maths, and often this is because they don't know the logic implicit in it.

I know there are some people that can never hope to understand any logic, but teaching is better than doing nothing. If a very small percent of people can think a little bit more clearly, then for example we might have a bit fewer people who believe less deeply in certain religions, and then we might not have another 4 years of Bushitism.

Monday, November 22, 2004

Alpha, Beta, Gamma, ...

I thought there's only one person who choose this kind of names, but no, there's "Ms. Alpha Pau" in career centre...

Sunday, November 21, 2004


The names say it all


Friday, November 19, 2004

Google Scholar

I don't know why, but Google even have the interest to specifically index academic publications...

Thursday, November 18, 2004


有 環 保 分 子 到 立 法 會 抗 議 紅 灣 半 島 可 能 拆 卸 , 說 會 製 造 大 量 建 築 廢 料 , 我 覺 得 香 港 有 些 環 保 分 子 做 事 情 已 經 走 過 了 頭 。 拆 卸 房 屋 會 製 造 建 築 廢 料 , 這 是 不 是 說 香 港 就 不 該 市 區 重 建 ? 製 造 建 築 廢 料 會 有 甚 麼 問 題 ? 實 際 上 這 些 廢 料 都 是 填 海 的 好 材 料 , 今 日 的 垃 圾 堆 填 區 就 是 將 來 的 土 地 , 香 港 地 小 人 多 , 多 製 造 幾 個 垃 圾 堆 填 區 , 將 來 多 一 些 土 地 , 有 甚 麼 不 好 ? 今 日 我 家 對 面 就 是 一 大 片 由 垃 圾 堆 填 出 來 的 大 草 地 , 面 對 青 翠 的 綠 草 地 , 賞 心 悅 目 。
曾 淵 滄
蘋果日報 18/11/2004

好呀, 不如拆左國金, 擎天半島之類啦, 督眼督鼻, 是填海的好材料...
我最憎市區重建局. 最好好似菠蘿油王子裡面咁, 自行解體...

昨晚之中港科馬大戰真是精采, 可謂:

X方日報真係「愛國」得好緊要, 頭條竟然話范俊業撲出十二碼係「逞強」... 咁係咪要企定定俾你射?

Tuesday, November 16, 2004

在棺材裏,阿拉法會嘲笑這位「老朋友」:「對以色列,我一寸土地也不讓 --- 加沙地帶、約旦河西岸、戈蘭高地。但是,你們的釣魚台、黑瞎子島、烏蘇里江和黑龍江外的一千五百個香港的領土呢?回去吧,我不要你來弔唁,你還有臉來鞠躬?」

蘋果日報 2004-11-13

Wednesday, November 10, 2004




強伯今天罷寫一日 (請勿給稿費), 希望引起高層注意, 正視此事.

強伯 -- 厭倦了沉默, 大方, 視而不見

某人也許食得豬油太多, 面皮太厚, 除繼續抄笑話, 今天的"專欄"更是"精采":

好 友 廖 先 生 的 公 子 在 倫 敦 留 學 , 廖 太 太 時 常 要 去 那 小 住 幾 天 , 陪 伴 兒 子 到 外 邊 吃 吃 飯 , 問 我 有 甚 麼 好 介 紹 。
倫 敦 的 餐 廳 多 不 勝 數 , 重 要 的 是 看 想 吃 些 甚 麼 菜 。
「 記 得 你 說 過 有 個 地 下 鐵 站 附 近 的 意 大 利 餐 廳 不 錯 , 不 知 道 叫 甚 麼 ? 」 廖 公 子 問 。
「 哦 , 那 應 該 是 一 家 叫 Metrogusto 的 , 地 址 是 13, Theberton Street, N1 , 電 話 號 碼 : 020 7226 9400 。 」
「 還 有 甚 麼 好 意 大 利 菜 ? 」

「 另 外 一 家 叫 The River Cafe , 被 譽 為 意 大 利 之 外 最 意 大 利 的 , 地 址 是 Thames Wharf, Rainville Road, W6 , 電 話 : 020 7386 4200 。 」
「 印 度 菜 呢 ? 」
「 印 度 餐 廳 在 倫 敦 比 其 他 城 市 多 , 英 國 人 已 經 把 印 度 菜 當 成 自 己 國 家 菜 , 就 像 荷 蘭 人 認 印 尼 菜 是 國 寶 一 樣 , 很 出 色 的 有 一 家 叫 Rasa Samudra 的 , 地 址 是 : 5, Charlotte Street W1 , 電 話 : 020 7637 0222 。 」
「 吃 肉 呢 ? 」
「 吃 肉 的 餐 廳 , 有 甚 麼 比 在 肉 市 場 附 近 更 好 ? 在 Smithfield Meat Market 附 近 的 那 家 St. John 可 以 試 試 看 。 地 址 是 : 26, St. John Street, EC1 , 電 話 : 020 7251 0848 。 」
「 有 哪 一 間 是 最 古 老 的 ? 」
「 倫 敦 最 古 老 的 餐 廳 叫 Rules , 地 址 是 : 35, Maiden Lane WC2 , 電 話 : 020 7836 5314 。 」
「 還 有 甚 麼 吃 的 可 以 推 薦 ? 」
「 到 英 國 , 當 然 要 嘗 嘗 英 國 人 覺 得 最 自 豪 的 魚 條 薯 條 Fish & Chips 了 , 可 去 Rock And Sole Place 。 地 址 是 : 47, Endell Street, WC2 , 電 話 : 020 7836 3785 。 想 到 其 他 菜 , 再 打 電 話 來 。 」 我 說 。

Friday, November 05, 2004


司徒華,蘋果日報 03/11/2004

Tuesday, November 02, 2004

Thursday, October 28, 2004

A: "麥兜波蘿油王子"好唔好睇?
B: 唔好! 都唔好笑,悶死!

* * *


* * *



Tuesday, October 26, 2004

Check your collaboration distance with...

MathSciNet has added the functionality to search the collaboration distance between any two authors! Now you can search your distance with Erdos, Einstein, ... easily.

Tuesday, October 19, 2004


From 太陽報:


Sunday, October 17, 2004

Mutually Exclusive Thoughts

For some reason, students tend to think that certain things are mutually exclusive when they are not:

1. They think that "deterministic finite automata" and "nondeterministic finite automata" are disjoint sets, thus feel puzzled when someone says "a deterministic FA is also a nondeterministic FA". This is probably not their fault; the names really sound like they are opposites.

2. Then we have students who think that a strongly-connected graph is not a weakly-connected graph, even though the definition clearly shows that it is. OK, strong and weak are opposites...

3. Now we have students who think that there are 3 types of functions: injective, surjective, and bijective, and a function must belong to exactly one type. I dunno how they can get this impression.

I am waiting some students to say "a tree is not a graph", or something like that.

Thursday, October 14, 2004

This is year 2046. Two computer science professors at MIT is chatting.

Young Prof A: The standard of students is really too bad. Today I see a grad student from Hong Kong. He said he's never heard of the principle of inclusion-exclusion.

Old Prof B: This is not too bad. You don't know the effort required to clear their wrong understanding about the congruence modulo symbol in my cryptography class.

A: Worst still, he doesn't know what are floors and ceilings!

B: This happens all the time. Some 40 years ago I met a grad student from Hong Kong. He complained exactly the same thing you just said, and mentioned the interesting thing that students can do dynamic programming of matrix chain multiplication without knowing how to multiply two matrices together.

A: Oh really?

B: He also regretted that his teachers didn't teach enough basic stuff, like elementary graph algorithms, generating functions, pumping lemma, and so on.

A: Er - sorry - did you say "pumping lemma"? What's it?

Friday, October 08, 2004


沙田區某愛國愛港組織(?), 在香港文化博物館附近, 掛出極具"文化 x x x "氣息的這些東西. 至於為何下半旗, 就...

Tuesday, October 05, 2004

I have never seen anything as "sensible" as this before:

To ensure that your published works are easily retrievable and identifiable by the widest possible readership, I wish to remind all staff to give the address of this University i.e. "The University of Hong Kong, Pokfulam" in their publications.

The addition of "Pokfulam" after the University's name is very important because an online search for the "University of Hong Kong", "Hong Kong University", or a similar variant will show up other tertiary institutions in Hong Kong due to the "generic" nature of our name. The inclusion of "Pokfulam" in the University's address will therefore ensure that searches are confined to outputs published by this University.

University of California, Berkeley? So what are the other campuses of HKU, huh?

新世界(17)旗下之移動雪櫃(970)表示, 雖然近期油價高企, 但該公司不會節約能源, 仍會維持車廂超低温.