Download presentation

Presentation is loading. Please wait.

Published byAlex Hambleton Modified over 2 years ago

2
GRAFOTYP Project financed by the Ministry of Science and Higher Education in Poland from funds on science in years 2009 – 2011 as development project Authors of software: Andrzej Łuszczuk M.Sc. Krystyn Łuszczuk M.Sc. Eng. Scientific consultation: Prof.Tadeusz Tomaszewski Dr Mieczysław Goc English version: Agnieszka Łukomska (M.A.) Software producer and distributor: Research and Training Centre of Polish Forensic Association www.kryminalistyka.pl Programme Guide The Polish ForensicAssociation University of Warsaw

3
The p rogramme applies : graphometrical examined method, basic notions: shape coefficient, size proportion, Grafotyp, Grafotypes match. Which were worked out by authors of programme. The p rogramme applies : graphometrical examined method, basic notions: shape coefficient, size proportion, Grafotyp, Grafotypes match. Which were worked out by authors of programme.

4
System and equipment requirements: TO ENSURE PROPER RUNNING OF PROGRAMME THE FOLLOWING REQUIREMENTS SHOULD BE MET: 1.Operating system: Windows XP, Windows Vista, Windows 7 or Windows 8. 2. IMPORTANT: required monitor (display) resolution 1024 × 600 or higher. In lower resolution, the programme cannot be started. In lower resolution, the programme cannot be started. 3. Recommended default font size "9" at 96 dpi (not more than 120 dpi). 4. In Windows „.NET Framework" platform in v.2.0.50727 or more recent version should be installed. It is necessary for proper running of the programe. should be installed. It is necessary for proper running of the programe.

5
Definitions: G = Wk × Pw Specimens - corresponding fragments of handwriting "A" and "B" selected for analysis, e.g. syllab l e, morpheme, word, illegible construction (signature). Specimens - corresponding fragments of handwriting "A" and "B" selected for analysis, e.g. syllab l e, morpheme, word, illegible construction (signature). Shape coefficient (Wk) - structural parameter of handwriting expressed through quotient of area of a polygon, constituting "contour" of the area of specimen selected for analysis (questioned and reference material) by square circumference of that polygon Wk = Σ | F | / (ΣL^2). For specimen A - shape coefficient (Wka) and for specimen B - shape coefficient (Wkb). Shape coefficient (Wk) - structural parameter of handwriting expressed through quotient of area of a polygon, constituting "contour" of the area of specimen selected for analysis (questioned and reference material) by square circumference of that polygon Wk = Σ | F | / (ΣL^2). For specimen A - shape coefficient (Wka) and for specimen B - shape coefficient (Wkb). Size proportion (Pw) - quotient of lenghts (shorter to longer) of two, most characteristic segments in specimens "A" and "B" (horizontal, vertical or slanting) set according to the same criteria, i.e. these segments should link corresponding points in specimens "A" and "B". Grafotyp (G) - structural property of handwriting, individualizing its writer. Mathematically it constitutes a product of shape coefficient (Wk) and size proportion (Pw). Grafotyp (G) - structural property of handwriting, individualizing its writer. Mathematically it constitutes a product of shape coefficient (Wk) and size proportion (Pw). Grafotyp similarity (%) - percentage rate of structural shape similarity between specimens "A" and "B", which demonstrates the authorship similarity. Mathematically it constitutes a quotient of Grafotypes (lower to higher value) multiplied by 100%. Grafotyp similarity (%) - percentage rate of structural shape similarity between specimens "A" and "B", which demonstrates the authorship similarity. Mathematically it constitutes a quotient of Grafotypes (lower to higher value) multiplied by 100%.

6
l 15 l 17 l6l6 l5l5 l4l4 l3l3 l2l2 l1l1 l 13 l 12 l 11 l 10 l9l9 l8l8 l7l7 l 16 l 14 Circumference „of contour” P = l 1 +l 2 +l 3 +…+l 15 +l 16 +l 17 (sum of lenghts of red segments) Shape coefficient Wk = 100 * F / P² Size proportion Pw = W 1 / W 2, where: 0 < Pw <= 1 Surface (green) „of contour” = F GRAFOTYP G = Wk × Pw W2W2W2W2 W2W2W2W2 W1W1W1W1 W1W1W1W1 F GRAFOTYP – method of calculation

7
GRAFOTYP GRAFOTYP GRAFOTYP allows for evaluation of degree of similarity between handwriting specimens basing on the following: 1.Shape coefficients match Wk 2.Size proportion Pw 3.Grafotypes match G GRAFOTYP allows for evaluation of degree of similarity between handwriting specimens basing on the following: 1.Shape coefficients match Wk 2.Size proportion Pw 3.Grafotypes match G

8
– interface (specimens prepared for examination) GRAFOTYP – interface (specimens prepared for examination)

9
Specimens after analysis – positive verification Shape coefficients match Grafotypes match Shape coefficient of specimen A Shape coefficient of specimen B Message of quantile test

10
Shape coefficient of specimen A Shape coefficient of specimenB Shape coefficients match Grafotypes match Message of quantile test Specimens after analysis – negative verification

11
Notes on statistical test applied : A quantile statistical test, used in the programme, is entirely independent from Wk, Pw values calculated before and Grafotypes. It is necessary for the specimen "contour" polygon to have from 6 up to 30 (optimally around 20) sides. Quantile test constitutes a separate examination method. If the test demonstrates a proper distribution of quotients of corresponding sides, this may attest for a match of shapes of specimens’ „contours”. If the test demonstrates a proper distribution of quotients of corresponding sides, this may attest for a match of shapes of specimens’ „contours”. The test helps expert in making such decision. Furthermore, the test serves as a certain verification of earlier measurements. Quantile test constitutes a separate examination method. If the test demonstrates a proper distribution of quotients of corresponding sides, this may attest for a match of shapes of specimens’ „contours”. If the test demonstrates a proper distribution of quotients of corresponding sides, this may attest for a match of shapes of specimens’ „contours”. The test helps expert in making such decision. Furthermore, the test serves as a certain verification of earlier measurements. If, for instance, the test will show the possibility of match between specimens at low Grafotype similarity, this provides for inaccurate or wrong designation of "contours", W1-W2 segments in particular. In such instances the analysis should be repeated. If, for instance, the test will show the possibility of match between specimens at low Grafotype similarity, this provides for inaccurate or wrong designation of "contours", W1-W2 segments in particular. In such instances the analysis should be repeated.

12
The following messages of quantile test can appear as result of analysis:

13
Basic principles of verification of handwriting specimens in GRAFOTYP Statistical certainty of verification increases with the number of sides in „contour” polygons. GRAFOTYP is a measuring tool, which examines geometrical shape of specimens. It does not account for other features (such as tremor, points of stoppage, shading distribution) which may appear in examined specimens and be in conflict with high geometrical similarity. (such as tremor, points of stoppage, shading distribution) which may appear in examined specimens and be in conflict with high geometrical similarity. PROGRAMME IS A MEASURING TOOL AND DOES NOT INTEND TO SUBSTITUTE THE EXPERT A final decision on match of examined entries belongs to the user !!! GRAFOTYP is a measuring tool, which examines geometrical shape of specimens. It does not account for other features (such as tremor, points of stoppage, shading distribution) which may appear in examined specimens and be in conflict with high geometrical similarity. (such as tremor, points of stoppage, shading distribution) which may appear in examined specimens and be in conflict with high geometrical similarity. PROGRAMME IS A MEASURING TOOL AND DOES NOT INTEND TO SUBSTITUTE THE EXPERT A final decision on match of examined entries belongs to the user !!!

14
You are welcome to use our programme

Similar presentations

OK

Math Vocabulary PowerPoint Jahsaun arnett. in·te·ger integer A member of the set of positive whole numbers { 1, 2, 3,... }, negative whole numbers {-1,

Math Vocabulary PowerPoint Jahsaun arnett. in·te·ger integer A member of the set of positive whole numbers { 1, 2, 3,... }, negative whole numbers {-1,

© 2017 SlidePlayer.com Inc.

All rights reserved.

Ads by Google