My life is an open book.
What the machine learning people I follow on Twitter are reading.
And a custom paper.
I was looking at some prediction results for the UCI Michalski and Chilausky soybean data set and wondered how they depended on test set selection. Some had classification accuracy as high as 93.1% accuracy on a 25% training set and 97.1% on 290 training and 340 test instances.
A few weeks ago I had been asked to find the best classifier for the soybean data set based on test set of 20% of the data. The remaining 80% could be used for training. That gave 306!/(245!x61!) = 1.3 x 10^65 possible splits of the 306 data points into training and test sets. Could some of these splits lead to better results than others for the classifiers I was about to use?
The WEKA data mining package was used for classification. WEKA has many classifiers that can be run on a data set and their performance to be compared.
WEKA also has a programming interface so I used it to write some Jython tools to explore the performance of a range of classifiers.
One of these tools was run on the soy-bean data to find the training/test splits with best and worst classification accuracy. The results were
| Classifier | Best Accuracy | Worst Accuracy |
|---|---|---|
| Naive Bayes | 100% | 70.5% |
| Bayes Net | 100% | 75.4% |
| J48 (C4.5) | 95% | 69% |
| JRip (RIPPER) | 98.4% | 70.5% |
| KStar | 96.7% | 65.6% |
| Random Forest | 95% | 62.3% |
| SMO (support vector machine) | 96.7% | 82% |
| MLP (neural network) | 100% | 77% |
| Classifier | Correct (out of 60) | Percent Correct |
|---|---|---|
| Naive Bayes | 57 | 95 % |
| Bayes Net | 59 | 98.3 % |
| J48 | 58 | 96.7 % |
| JRip | 60 | 100 % |
| KStar | 60 | 100 % |
| Random Forest | 59 | 98.3 % |
| SMO | 60 | 100 % |
| MLP | 60 | 100 % |
Someone was asking questions about const_cast<>() a few days ago. I was not quite sure how it would work because I try to use as little of the C++ language as possible and it possible to get by in C++ without const_cast<>(). To find out exactly how it worked I tried it out with a test case. The following code gave the same output on g++ on Vista and OS X.
The output in both cases was Cannot happen: &i=0x22fe6c == ptr=0x22fe6c but i=3 != *ptr=22
int i = 3;
const int* ptr = &i;
*const_cast<int*>(ptr) = 11;
if (&i == ptr && i != *ptr) {
std::cout << "Cannot happen: &i=" << &i << " == ptr=" << ptr << " but i=" << i << " != *ptr=" << *ptr << std::endl;
}
push %ebp
mov %esp,%ebp
sub $0x18,%esp
int i = 3;
movl $0x3,0xfffffffc(%ebp) (i in bp-4)
const int* ptr = &i;
lea 0xfffffffc(%ebp),%eax (&i in eax)
mov %eax,0xfffffff8(%ebp) (ptr in bp-8)
*const_cast<int*>(ptr) = 11;
mov 0xfffffff8(%ebp),%eax (ptr in eax)
movl $0xb,(%eax) (*ptr set to 11)
if (&i == ptr && i != *ptr)
lea 0xfffffffc(%ebp),%eax
cmp 0xfffffff8(%ebp),%eax
jne 0x403214
mov 0xfffffff8(%ebp),%eax
mov (%eax),%eax
cmp 0xfffffffc(%ebp),%eax
je 0x403214
I lived in Sweden from 1988 to 1991. Here is a map which showed where I lived in Stortorget in Gamla Stan in Stockholm.
View Larger Map
I lived in the red building in the two left photos below which are taken from Stortorget. The photo on the right is of the same building taken from Kåkbrinken, the alley to the left the red building.
The photo on the left below is the main street in Gamla Stan and the photo on the centr is of the Grand Hotel as seen from the shore of Gamla Stan and the photo on the right is Karloniska Hospital where I worked.
After I left Stockholm I moved to Umeå which is shown on the left below. When I lived there I used to visit Vaasa in Finland shown on the right.
When I lived in Sweden I took vacations in Norway including Lofoten on the left and Tromsø in the centre of the row of photos below. I also took the Hurtigruten
I am setting up Postfix so I have spare time as I try things out. This post is about the things I am reading or watching in the background.
Taskforce on Context-Aware Computing
I went to a lecture called Open Mobile Miner (OMM): A System for Real Time Mobile Data Analysis. There is a video here, a description of OMM here and lecture slides here (pdf).
Shonali Krishnaswamy's group are making software that does some analysis of data on a smart phone before uploading it, thereby reducing the phone's power consumption by reducing communications. Their examples include ECG output, traffic congestion metrics and taxi location data. The data in their examples is scalar and sampled at 0.5 Hz or less so it is hard to see why a simple store-and-forward scheme would not achieve much the same thing. I guess I need to read their publications more deeply.
Statistical Learning as the Ultimate Agile Development Tool by
Peter Norvig is an overview of modern practical machine learning. The summary is focus on the data, not the code.
Learning Theory by
Mark Reid was an introduction to some theoretical aspects of machine learning presented in a summer school in Canberra in January 2009.
˙ʇǝsdıɥɔ pǝsɐq ɯɹɐ s’ǝןɐɔsǝǝɹɟ 'uoƃɐɹpdɐus ɯɯoɔןɐnb 'ɯoʇɐ ןǝʇuı ˙sɹɐʍ ɹossǝɔoɹd ˙sʞooqʇǝu puɐ sǝuoɥd ʇɹɐɯs ɟo ǝɔuǝƃɹǝʌuoɔ ǝןqıssod ˙ǝƃuɐɥɔ ǝʌıɹp ןןıʍ ǝɔuǝɹǝɟɟıp ǝɔıɹd 000'1$ ˙sʌ 052$ ǝɥʇ ˙pǝʇıns-ןןǝʍ os ʇou sǝop pɹoʍ ʇɟosoɹɔıɯ ǝןıɥʍ pnoןɔ ǝɥʇ ɯoɹɟ ןןǝʍ sʞɹoʍ ʎpɐǝɹןɐ ǝɹɐʍʇɟos ɹǝɥʇo puɐ uozɐɯɐ 'ɯoɔ˙ǝɔɹoɟsǝןɐs 'ǝןƃooƃ ˙ǝɹɐʍʇɟos ʇɟosoɹɔıɯ ǝɥʇ doʇdɐן ǝɔɐןdǝɹ ʎɐɯ pnoןɔ + ʞooqʇǝu os ƃuıʇndɯoɔ pnoןɔ oʇ pǝʇıns-ןןǝʍ ǝɹɐ sʞooqʇǝu ˙ʇɟosoɹɔıɯ puɐ ןǝʇuı oʇ ʇsoɔ ʇɐǝɹƃ ʇɐ sǝןɐs doʇdɐן 0001$sn ǝzıןɐqıuuɐɔ ʎɐɯ sʞooqʇǝu 052$sn ɯɹǝʇ ɹǝƃuoן ǝɥʇ uı ʇnq ǝıd ɔd ǝɥʇ ƃuıʍoɹƃ ǝɹɐ sʞooqʇǝu ʎןʇuǝɹɹnɔ ¿uıɐɥɔ ǝnןɐʌ doʇdɐן puɐ ɔd ǝɥʇ oʇ op sʞooqʇǝu ןןıʍ ʇɐɥʍ ˙sǝןɐs ƃuıʇsıxǝ ɟo uoıʇɐzıןɐqıuuɐɔ pnoןɔ ǝɥʇ oʇ ʇuǝɯǝʌoɯ ɟo sǝɔuǝnbǝsuoɔ ǝɯos sɹoʇıʇǝdɯoɔ ɹıǝɥʇ ɹǝʌo ǝƃɐʇuɐʌpɐ ƃuıɔıɹd ɐ ǝʌǝıɥɔɐ ןןıʍ sıɥʇ ǝpıʌoɹd uɐɔ oɥʍ sɹǝıɹɹɐɔ uoıʇɐɔıunɯɯoɔǝןǝʇ ǝɥʇ ˙suoıʇɔǝuuoɔ ʞɹoʍʇǝu ǝןqɐʇɹod puɐ ǝןqɐıןǝɹ 'ʇsɐɟ sǝɹınbǝɹ ƃuıʇndɯoɔ pnoןɔ ʎɥdɹnɯ ˙ɹɯ sʎɐs „'ɹǝʇʇǝq ʇnq ƃuıɥʇou uǝǝq s,ʇı 'dɯnɥ ƃuıuɹɐǝן ǝɥʇ ɹǝʌo ʇoƃ ǝʍ ǝɔuo ˙sǝƃɐʇuɐʌpɐsıp ןɐǝɹ ʎuɐ ɥʇıʍ dn ƃuıɯoɔ pǝssǝɹd-pɹɐɥ ǝq p,ı ˙ǝɹoɯ ʎuɐ suoıʇɐןןɐʇsuı ǝɹɐʍpɹɐɥ ןɐɔısʎɥd ɹoɟ ƃuıʇıɐʍ sʎɐp puɐ sɹnoɥ puǝds ʇ,uop ǝʍ„ ˙sɹǝʇndɯoɔ uʍo sʇı ɟo ǝuou ɥʇıʍ ʎuɐdɯoɔ ʇuǝɯdoןǝʌǝp qǝʍ ɐ ǝɯoɔǝq sɐɥ ʇı - ǝɹɐʍpɹɐɥ ןɐɔısʎɥd ɹoɟ ʇno ƃuıʞɹoɟ pǝddoʇs sɐɥ ʇı suɐǝɯ ɥɔıɥʍ 'ǝɔıʌɹǝs ןɐnʇɹıʌ ǝɥʇ ɹoɟ ɹnoɥ ɹǝd sʇuǝɔ 08 oʇ 01 sʎɐd ǝƃuɐɹo ʎɔınɾ ˙ǝɯoɔǝq sɐɥ ƃuıʇndɯoɔ pnoןɔ ɯɐǝɹʇsuıɐɯ ʍoɥ sǝʇɐɹʇsnןןı (9002 qǝɟ 02 ǝƃɐ ǝɥʇ) ɯɐǝɹʇsuıɐɯ ǝɥʇ spuǝɔsɐ ƃuıʇndɯoɔ pnoןɔ ”˙ƃuıʍoɹƃ ןןıʇs sı ןɐɹǝuǝƃ uı ƃ3“ ˙sʇdǝɔuoɔ pɹɐʍɹoɟ ʇɐ ןɐdıɔuıɹd 'ssnɐɹʇs ןןıʍ pıɐs ”'sʇods ʇɥƃıɹq ǝɹɐ ǝsǝɥʇ“˙˙˙ ˙pǝʌɹǝsqo ǝʌɐɥ sʇsʎןɐuɐ 'ǝɔuɐɥɔ ƃuıʇɥƃıɟ ɐ ǝʌɐɥ sɯǝpoɯ ƃ3 puɐ sdıɥɔ ɥʇooʇǝnןq puɐ ıɟ-ıʍ 'sdƃ ǝʞɐɯ oɥʍ sɹopuǝʌ puɐ — ɥʇʍoɹƃ ʇɐɥʇ ɟo ɥʇƃuǝɹʇs ǝɥʇ uo ʎɹɐʌ sʇsʎןɐuɐ — ɹɐǝʎ sıɥʇ ʍoɹƃ oʇ pǝʇɔǝɾoɹd ǝɹɐ sǝןɐs ǝuoɥdʇɹɐɯs ˙pɐǝɥɐ ɹɐǝʎ ǝɥʇ uı sʇods ʇɥƃıɹq ƃuıʞǝǝs puɐ sɥʇƃuǝɹʇs ǝɹoɔ oʇ ƃuıʞooן ǝɹɐ sɹopuǝʌ dıɥɔ ʇsoɯ 'ǝןıɥʍuɐǝɯ˙˙˙ ˙sʇǝʞɹɐɯ ʍǝu uǝdo oʇ ʎɐןd ǝuoɥd ʇɹɐɯs ɐ ƃuıɹɐdǝɹd ǝq oʇ pǝɹoɯnɹ sı ˙ɔuı ןןǝp ɹǝʞɐɯ ɔd ˙ǝuoɥdı s’˙ɔuı ǝןddɐ ʎq pǝʌɹǝs ʇǝʞɹɐɯ ǝɥʇ ɟo ǝɯos qɐɹƃ oʇ ƃuıdoɥ 'ʍoןs sǝʇɐɹ sǝןɐs ɔd sɐ spıɯ pǝʇǝƃɹɐʇ sɐɥ — ɹǝʞɐɯ dıɥɔ ʇsǝƃɹɐן s’pןɹoʍ ǝɥʇ — ˙dɹoɔ ןǝʇuı sɐ 'uoıʇıʇǝdɯoɔ ǝʌɐɥ ןןıʍ ɯɯoɔןɐnb˙˙˙spןǝɥpuɐɥ puɐ sdoʇdɐן uǝǝʍʇǝq dɐƃ ǝɔıɹd ǝɥʇ ǝƃpıɹq sʞooqʇǝu sɐ ǝƃɹns oʇ pǝʇɔǝɾoɹd ʎɹoƃǝʇɐɔ ɹǝʇʇɐן ǝɥʇ ɥʇıʍ 'sǝɔıʌǝp ʇǝuɹǝʇuı ǝןıqoɯ puɐ sʞooqʇǝu 'sʞooqǝʇou ɹoɟ ʇǝsdıɥɔ uoƃɐɹpdɐus sʇı uo sısɐɥdɯǝ pǝɔɐןd sɐɥ ɯɯoɔןɐnb 'ǝןıɥʍuɐǝɯ sdıɥɔ :ʇsɐɔǝɹoɟ ssǝןǝɹıʍ 9002 ssǝןǝɹıʍ ɹɔɹ sǝuıɥɔɐɯ dx sʍopuıʍ ɹo nʇunqn ʎןןɐnsn ǝɹɐ ʇɐɥʍ ƃuoɯɐ ǝɥɔıu ɐ puıɟ ןןıʍ ɯɹoɟʇɐןd ǝןıqoɯ ǝɔɹnos-uǝdo s’ǝןƃooƃ ʇɐɥʇ ƃuıʇʇǝq sı - ʎɐpoʇ ʇǝʞɹɐɯ ǝɥʇ uo sʞooqʇǝu ɟo ʎʇıɹoɾɐɯ ʇsɐʌ ǝɥʇ uı punoɟ ɹossǝɔoɹd 072u ɯoʇɐ ןǝʇuı ǝɥʇ ɹoɟ ǝןqısuodsǝɹ - ɹǝʞɐɯdıɥɔ ǝɥʇ ʇɐɥʇ sʇsǝƃƃns oɥʍ '”ǝɔɹnos ǝןqɐıןǝɹ“ s’ʇɐǝqǝɹnʇuǝʌ oʇ ƃuıpɹoɔɔɐ s’ʇɐɥʇ ˙ǝɹɐʍpɹɐɥ ʇǝsdıɥɔ ǝןqɐʇıns ɥʇıʍ sɹǝɹnʇɔɐɟnuɐɯ ʇɹoddns oʇ ƃuıɹɐdǝɹd sı puɐ '0102 ʇnoɥƃnoɹɥʇ puɐ 9002 ǝʇɐן uı sʞooqʇǝu pǝsɐq-pıoɹpuɐ ɟo ʎɹɹnןɟ ɐ ƃuıʇɔǝdxǝ sı ןǝʇuı sʞooqʇǝu pǝsɐq-pıoɹpuɐ ɟo ǝsıɹ ɹoɟ ƃuıʎpɐǝɹ ןǝʇuı ʞooqʇǝu pǝsɐq-pıoɹpuɐ ɟo ǝsıɹ ɹoɟ ƃuıʎpɐǝɹ ןǝʇuı ʎoʎ %6˙12– puɐ bob %7˙12– pǝuıןɔǝp sʇuǝɯdıɥs ʇıun ɹossǝɔoɹd ɔd ǝpıʍpןɹoʍ 'ɯoʇɐ ʇnoɥʇıʍ ˙ǝuıןɔǝp ɔıʇɐɯɐɹp pıoʌɐ ʇǝʞɹɐɯ ǝɥʇ dןǝɥ oʇ ɥƃnouǝ ʇou ʇnq ǝɔuɐɯɹoɟɹǝd ʇǝʞɹɐɯ ןןɐɹǝʌo ǝɥʇ uı ǝɔuǝɹǝɟɟıp ǝןqɐʇou ɐ ǝʞɐɯ oʇ pǝnuıʇuoɔ (,,sʞooqʇǝu,, sןןɐɔ ןǝʇuı ɥɔıɥʍ) sɔd ʞooqǝʇou-ıuıɯ ɹoɟ ɹossǝɔoɹd ɯoʇɐ s,ןǝʇuı ˙˙˙ ؛(ʎoʎ) ɹɐǝʎ ɹǝʌo ɹɐǝʎ %4˙11– puɐ (bob) ɹǝʇɹɐnb ɹǝʌo ɹǝʇɹɐnb %0˙71– pǝuıןɔǝp sʇuǝɯdıɥs ʇıun ɹossǝɔoɹd ɔd ǝpıʍpןɹoʍ '80b4 uı 80b4 uı sʞooqʇǝu oʇ sdoʇdɐן sʍopuıʍ ɯoɹɟ ǝʌoɯ sıɥʇ ʇɹoddns oʇ sǝıɹoʇs ǝɯos ǝɹɐ ǝɹǝɥ ˙ʎʇıןıqoɯ puɐ ʎɹʇsǝɔuɐ ǝuoɥd ɹıǝɥʇ ɯoɹɟ sǝɯoɔ ʇɐɥʇ uoıʇdɯnsuoɔ ɹǝʍod ʍoן ɟo sǝƃɐʇuɐʌpɐ ןɐuoıʇıppɐ ǝɥʇ ǝʌɐɥ ʎǝɥʇ ˙sƃuıɹǝɟɟo pnoןɔ ɹǝɥʇo puɐ uoıʇɐzıןɐnʇɹıʌ 'sɐɐs 'sǝɔıʌɹǝs qǝʍ ɹoɟ sʇuǝıןɔ ǝʇɐnbǝpɐ ǝʞɐɯ ǝuoɥd ʇɹɐɯs ǝןqɐdɐɔ ʎɹǝʌ puɐ sʞooqʇǝu ƃ3 ˙sǝıƃǝʇɐɹʇs ƃuıʇndɯoɔ doʇʞsǝp pǝnsɹnd ʇou ǝʌɐɥ puɐ sǝɔıʌɹǝs ɟo sǝdʎʇ ǝsǝɥʇ uo ʎןǝɹıʇuǝ sǝssǝuısnq ɹıǝɥʇ pǝsɐq ǝʌɐɥ oɥʍ ɯoɔ˙ǝɔɹoɟsǝןɐs puɐ ǝɹɐʍɯʌ 'ǝןƃooƃ sɐ ɥɔns sǝıuɐdɯoɔ ʎq uǝʌıɹp uǝǝq sɐɥ ʇuǝɯdoןǝʌǝp ɹıǝɥʇ ˙sɹɐǝʎ 01 ʇsɐן ǝɥʇ uı ǝʌıʇɔǝɟɟǝ ʎןɥƃıɥ ǝɯoɔǝq ǝʌɐɥ ǝsǝɥʇ ɟo ʇsoɯ ˙ suoıʇɐɔıןddɐ qǝʍ puɐ sɐɐs 'uoıʇɐzıןɐnʇɹıʌ ƃuıpnןɔuı sǝɔıʌɹǝs pnoןɔ ɟo sǝdʎʇ ʎuɐɯ ǝɹɐ ǝɹǝɥʇ ˙uoıʇɐzıuɐƃɹo uɐ ɥƃnoɹɥʇ pǝʇɐɔıןdǝɹ ǝq oʇ pǝǝu ʇou sǝop ǝƃɐɹoʇs ʞsıp ʎʇıןıqɐıןǝɹ-ɥƃıɥ sɐ ɥɔns ǝɹnʇɔnɹʇsɐɹɟuı ǝʌısuǝdxǝ ʇɐɥʇ ʇıɟǝuǝq ןɐuoıʇıppɐ ǝɥʇ sı ǝɹǝɥʇ ˙ʇuǝıɔıɟɟǝ ǝɹoɯ ɥɔnɯ sı ɹǝʌɹǝs ןɐɹʇuǝɔ ɐ uo ǝɹɐʍʇɟos ǝɥʇ ƃuıuunɹ ǝɹoɟǝɹǝɥʇ ˙%01 uɐɥʇ ssǝן ɥɔnɯ 'ʍoן ʎɹǝʌ sı ǝɹɐʍʇɟos sıɥʇ ɟo ǝƃɐsn ǝɔɹnosǝɹ ɹǝʇndɯoɔ ǝƃɐɹǝʌɐ ǝɥʇ ˙ǝʌısuodsǝɹ ǝq oʇ ǝɔɐɟɹǝʇuı ɹǝsn ǝɥʇ ʇuɐʍ noʎ puɐ suoıʇɐʇndɯoɔ ǝsuǝʇuı ǝɥʇ sǝop ʇı uǝɥʍ ʎɐp ɹǝd sǝʇnuıɯ ʍǝɟ ǝɥʇ 'ǝƃɐsn ʞɐǝd ʇɹoddns oʇ ƃuıʎɐd ǝɹɐ noʎ 'ʇı ʇɹoddns oʇ ǝɹɐʍpɹɐɥ ɔd ǝʌısuǝdxǝ ʎnq noʎ uǝɥʍ ˙ǝɯıʇ ǝɥʇ ɟo ʇsoɯ ƃuıɥʇou sǝop ʇı ˙sǝןɔʎɔ ʎʇnp ʍoן ʎɹǝʌ sɐɥ 'sɔıɥdɐɹƃ ʎʇıןɐnb ɥƃıɥ ǝʞıן ǝɹɐʍʇɟos ǝʌısuǝʇuı ʎןןɐuoıʇɐʇndɯoɔ uǝʌǝ 'ǝɹɐʍʇɟos ʇuǝıןɔ ʇsoɯ ˙sɹǝʇndɯoɔ ןɐuosɹǝd s,ǝןdoǝd ʎuɐɯ uo ʇı ƃuıop uɐɥʇ ɹǝısɐǝ sı uoıʇɐɔoן ןɐɔısʎɥd ǝuo uı ƃuıuunɹ ǝɹɐʍʇɟos ƃuıpɐɹƃdn puɐ ƃuıuıɐʇuıɐɯ ǝsnɐɔǝq uoıʇɐzıןɐɹʇuǝɔ ɥʇıʍ ʎןןɐɔıʇɐɯɐɹp sǝsɐǝɹɔǝp (oɔʇ) dıɥsɹǝuʍo ɟo ʇsoɔ ןɐʇoʇ ˙sʇuǝıןɔ ɹǝןןɐɯs ǝʌɐɥ puɐ ƃuıʇndɯoɔ ǝzıןɐɹʇuǝɔ-ǝɹ oʇ sı ʇı ǝsıɹdɹǝʇuǝ uı puǝɹʇ ɹoɾɐɯ ʇuǝɹɹnɔ ɐ
I could use one know for
Big Bucks in Health IT!, quoting from http://www.healthcareitnews.com/news/global-market-hospital-it-systems-pegged-35b-2015 , says
SAN JOSE, CA – The global hospital information systems market will climb past $35 billion by 2015, according to a new forecast by Global Industry Analysts. The United States represents the largest market in the world. The U.S. hospital information system market is experiencing an increase in acceptance of customized technology such as laboratory information systems and radiology information systems, the report notes. The market is also a promising ground for electronic medical record systems.
The Asia-Pacific region (excluding Japan) represents the fastest growing hospital information systems market, exhibiting a compounded annual growth rate of 11.5 percent over the next few years, according to analysts. Despite being a smaller market in terms of revenue, the Asia-Pacific promises excellent growth opportunities for hospital information systems, they said.
The global vendors profiled in the report include McKesson , Cerner , Allscripts-Misys Healthcare Solutions, Eclipsys, Computer Programs and Systems, Siemens Medical Solutions USA, QuadraMed, Medical Information Technology, Healthland, GE Healthcare, iSOFT Group, Agfa-Gevaert, Brunie-Software, IBA Health and Integrated Medical Systems.The full release is here: Global Hospital Information Systems Market to Cross $35 Billion by 2015, According to New Report by Global Industry Analysts, Inc. Increasing awareness among medical service patrons on the benefits of using Information Technology in the healthcare sector, coupled with growing demand for affordable-yet quality healthcare services is forcing hospitals and other medical centers to adopt IT in their daily operations. Subsequently, Healthcare IT systems such as the Hospital Information Systems witnessed a great demand in the healthcare services sector. Adoption of HIS in hospitals is increasingly being encouraged and promoted by the Governments world over. http://www.prweb.com/releases/2009/02/prweb2021984.htm
Where does http://bit.ly/peterwilliams direct to?
Is it the same web page as http://linkd.in/PeterWilliams ?
There has been a lot of talk about Open Government recently, including this from Peter Williams
"Australian governments should adopt international standards of open publishing as far as possible. Material released for public information by Australian governments should be released under a creative commons licence." or in simple terms "make public data open and free".That is useful, clear and straightforward.
A while back I worked at a company who made software+hardware products in a maturing market. The company found it needed to deliver higher quality products with more features and was struggling to do so from an old codebase. It had become clear to the management team that late-stage serious defects were the major cause of schedule/quality issues but they had been able to fix this problem.
The codebase management team had a lot of ideas about what the causes were and how to fix them. They had discussed "technical debt", "silo-ing" and other causes. However in the end they settled on two key priorities: taking extreme care with code changes and sticking with established QA processes to minimise the number of introduced bugs.
Eventually the project was given to me to manage. One of the (many) things the development team had done well was to document each bug and cross-reference bug fixes against the source code. I analysed about 100 recently fixed serious software bugs, looked up their fixes in the SCM and then looked up the date at which the code changes causing the bug were checked in. This showed that most of the bugs being found had been introduced months before they were discovered. It was clear that the late-stage defects were dominated by latent bugs being unmasked by changes, not by bugs introduced by changes.
Some changes to the development process were needed. The development group was responsible for creating code without introducing bugs and the QA group was responsible for finding the bugs the development team missed. However the QA process was unsuited to discovering latent bugs fast because it had a long cycle based on testing user scenarios. Therefore I got small teams of developers and QAs to work closely together to find, fix and verify bugs and I took some developers away other work to develop a system to find and fix (and eventually prevent the introduction of more) latent bugs. This work is described here. With these changes in place, code stability improved rapidly and late-stage serious bugs essentially ceased to be found.
That was a fairly straightforward technical solution to a fairly straightforward technical problem. So why had the very capable management team who had known the underlying causes (technical debt and silo-ing) not been able to fix the problem for so long?
Change is known to be difficult in organisations and there is an industry built around dealing with this. However our immediate problem was not an inability to persuade people to change. In fact consultation and review had been distracting people from doing the experimentation required to find the underlying causes of the problem was and how to fix them. The more people talked about the problem the further they got from the solution (hence this post's title).
The situation reminded me of Uncle Bob Martin's Agile Smagile
As I said before, going meta is a good thing. However, going meta requires experimental evidence. Unfortunately the industry has latched on to the word "Agile" and has begun to use it as a prefix that means "good". This is very unfortunate, and discerning software professionals should be very wary of any new concept that bears the "agile" prefix. The concept has been taken meta, but there is no experimental evidence that demonstrates that "agile", by itself, is good.The deeply ingrained practices in the organisation I worked in had grown out of ideas that had worked well in the past. They had been good enough to cover a wide range of development scenarios for a long while and were clearly based on experimental evidence from past development. However somewhere along the way people had stopped experimenting and modifying the rules, and started just following the rules. This is what Uncle Bob called "going meta". The problem for our organisation was that the set of rules it had got to when it stopped experimenting were not universally true, they were only true for the type of the development they were doing when they stopped changing the rules.
I recently read a stream of blog posts about why developers don't like C++ for general purpose programming. This post typifies much of the criticism of C++'s complexity. It includes an interview question about creating a C++ class that behaves like a class in a high level language such as Java. The author says that he uses this to weed out job applicants who haven't used C++ for real work.
It strikes me that tripping up developers with C++'s many oddnesses is much easier than that. Here is a simple question that I believe will confuse many non-C++ programmers:
What is the output of this program?
#include <string>
#include <iostream>
using namespace std;
class Parent {
public:
string func() { return "parent"; }
virtual string vfunc() { return "parent+virtual"; }
};
class Child : public Parent {
string func() { return "child"; }
virtual string vfunc() { return "child+virtual"; }
};
string test1(Parent parent) {
return parent.func() + " - " + parent.vfunc();
}
string test2(Parent& parent) {
return parent.func() + " - " + parent.vfunc();
}
int main() {
Child child;
cout << "test1: " << test1(child) << endl;
cout << "test2: " << test2(child) << endl;
}
I have seen C++ interviewers ask questions like this but only show test1 then ask what is on the stack when test1 is invoked.
Wolfram Alpha, the new computational knowledge engine from Wolfram Research has been getting a good run in the press this week so I decided to try it out.
It gave pretty good answers for most of the following queries. Try them out yourself.
It is often sad when software engineers are shown to be correct. One of my first posts was on monetizing social search
This innovative use of social networkingcould have a short-term payoff. It turns out to be one of the few successes to date in making money from social networking
NEVER anthropomorphize lusers.
But one company may have bitten and are close to buying the company. Sources are saying that the infamous Intelius (founded by the equally infamous Naveen Jain ), a people search engine that charges users to access data, may be buying Spock soon. If these rumors are accurate, God help Spock. Not only is Intelius embroiled in all kinds of legal and ethical disputes, but they also have a shaky history when it comes to acquisitions.Then Ajit Jaokar summed up
So, let me see if I get this right
a) Spock trawls the web looking for our data
b) It creates a profile about us in their site without approval
c) It encourages us to enrich that information
d) It charges us to access our own information
e) And ultimately .. it sells that same information to a background check company ..
For instance, my 'harnessed' profile (i.e. I did not create it) says .. Ajit Jaokar is an Indian-born British author and Web 2.0 specialist. He is the founder and CEO of the publishing company Futuretext. He is also the... and the rest you have to pay for :) (Don't bother .. that information is freely available on my blog .. and lots more .. so you can hopefully make your own judgements about me .. )
Can I delete my own information in Spock?.. Now it gets MUCH more interesting .. Spock says on deletion of information ..
If you'd like to remove yourself from Spock, please read the following information and click the link below.
Before requesting removal, please make sure the original source of the information Spock found for you has been removed or made private (MySpace, blog, Friendster, etc). This will prevent you from being re-indexed on the site. Please note that you can only request removal for your Spock search result.
When filling out your information please make sure to include your name, e-mail, a link to your Spock Search Result (i.e. http://www.spock.com/Tiger-Woods), and the reason why you'd like to be removed. The Spock Support Team will review your claim and get back to you within 24-48 hours.
So, I have to ensure that the Original sources of information that they got the profiles from should also be made private(i.e. my blog, my facebook profile etc etc) ..(else they will 'harness' me again!)
It is worth thinking about the future from time to time. It helps us craft investment strategies and career paths that match the major trends in the world. So what is the future of ICT?
SAP ERP systems effectively implemented can have huge cost benefits. Integration is the key in this process. "Generally, a company's level of data integration is highest when the company uses one vendor to supply all of its modules." An out-of-box software package has some level of integration but it depends on the expertise of the company to install the system and how the package allows the users to integrate the different modules.
A clear trend is emerging in the form of fixed and mobile telephony convergence (FMC). The aim is to provide both services with a single phone, which could switch between networks ad hoc. Several industry standardisation activities have been completed in this area such as the Voice call continuity (VCC) specifications defined by the 3GPP. Typically, these services rely on Dual Mode Handsets, where the customers' mobile terminal can support both the wide-area (cellular) access and the local-area technology (for VoIP). However, an alternative approach achieves FMC over 3G mobile networks - eliminating the requirement for Dual Mode. This approach, broadly termed cellular FMC, is in trials by telecoms operators including BT.
An alternative approach to achieve similar benefits is that of femtocells .Integration of simple cloud services
