Materials of the lecture on metrics and measures held by Programeter leadership during the Software Economics course at Tartu University: courses.cs.ut.ee/2010/se

1. Software Measurement Software Economics 2010

4. MSc in computer science at Tartu University

6. Are software metrics “ good ” or “ bad ”?

7. What is a “ measure ”?

8. What is a “measure”? “ Way of associating a number with some attribute of a physical object ” height -> meters temperature -> degrees Celsius

9. What is “measure”? One-to-one mapping between physical objects and formal objects (e.g numbers)

11. Relations on these objects ( e.g. more, equal )

15. Jobs and Ballmer can cooperate and put their apples together to have a larger pile

16. We defined a “ complete transition ” from “ real world ” into “ formal world ”

18. B be a relational system of formal objects ( e.g. numbers)

19. m be a measure from A to B then

21. For each operator in A there is a corresponding operator in B

22. Why is this important?

23. What Can You Say?

26. We don't have intuition for such cases

27. Intelligence Barrier

30. Anton : Yesterday was warmer than today

33. Statement is meaningful when it gives same result on all similar scales

34. Scales are similar when there is a transformation from one scale to another that retains all defined relations and operations

36. View from 3000 feet :) Nominal Scales Gender T-shirt Numbering

39. All Ordinal Scales Are Nominal Nominal Ordinal Gender T-shirt Numbering Top 100 Grading

42. Interval Scales Are Ordinal Nominal Ordinal Interval Gender T-shirt Numbering Top 100 Grading Temperature

45. Ratio Scales Are Interval Nominal Ordinal Interval Ratio Gender T-shirt Numbering Top 100 Grading Temperature Length Height

47. My software is 25 lines of code

48. Absolute Scales Are Ratio Nominal Ordinal Interval Ratio Absolute Scales Gender T-shirt Numbering Top 100 Grading Temperature Length Height Team Size

50. Quality is only ordinal (rarely interval)

53. In This Course: Metric = Measure

54. Software Metric is a measure of anything directly related to software or its production

57. Can anybody name any software metric?

59. Lines Of Code

61. Comments

63. Doesn't respect complexity and content

67. McCabe's Cyclomatic Complexity

69. n = 6

70. p = 1

71. V(G) = 3

75. Draw a flow graph

76. Calculate McCabe's cyclomatic complexity Code snippet

79. Object oriented metrics

81. Measure unique aspects of the object oriented approach

84. Complexity – Example RFC = 6, WMC = 1 + 2 + 1 = 4

86. Coupling – Example CBO = 2, LCOM = 3 – 0 = 3

87. Coupling – Example LCOM = 2 – 1 = 1

90. Object oriented metrics

91. Object oriented design quality metrics

94. Measure quality of an object oriented design

95. Can we divide dependencies into “ good ” and “ bad ”? Dependencies Between Classes

99. Easy to change = no dependents = irresponsible

101. Reused together

104. Example - Coupling Package One Package Two Package Three Ca(Package One) = 1, Ce(Package One) = 2

106. Stable -> I = 0 -> Ce = 0

107. Unstable -> I = 1 -> Ca = 0, Ce > 0

108. Should all categories be stable ?

109. Why a stable category needs to be extensible ? How?

111. Completely concrete -> A = 0 -> no abstract classes in category

112. Is there a relationship between Instability and Abstractness ?

113. Main Sequence

117. Object oriented metrics

118. Object oriented design quality metrics

119. Developer and team metrics

122. Churned LOC – number of added, modified and deleted lines of code

123. Churn Count – number of changes made to a file

124. Files Churned – number of changed files

135. Object oriented metrics

136. Object oriented design quality metrics

138. Knowledge

145. Unique: 2 / 5 -> 40% Shared: 1 / 5 -> 20% Unique: 1 / 5 -> 20% Shared: 1 / 5 -> 20%

149. Object oriented metrics

150. Object oriented design quality metrics

151. Developer and team metrics

152. Project size metrics

153. How would you measure product size?

155. Applied early ↔ Manual and subjective

157. Team specific

158. Applied early ↔ Manual and subjective

163. Object oriented metrics

164. Object oriented design quality metrics

165. Developer and team metrics

166. Project size metrics

167. Quality metrics

168. What does “ high quality ” mean? Quality Metrics

173. Architecture and design

175. Code coverage with tests

177. Delivery planning

179. Serves customer needs

182. Delays and troubles are not hidden

189. Course: IDY0204 “ Software Quality and Standards”

191. Examples of software metrics

192. Classification of software metrics

193. Classification of Software Metrics Subject of measurement

195. On the organizational level – strategic purposes

197. Number of changes in requirements

198. Number of finished tasks

199. Defect detection percentage

201. Developer fluctuation

202. Developer productivity and know-how in the project

203. Maturity of the code written by developer

205. McCabe's cyclomatic complexity

206. Code coverage with test

207. Code stability

208. Classification – Overview What is measured?

209. Classification of Software Metrics “ Lines of Code” vs “Quality”

211. McCabe's cyclomatic complexity

212. Number of requirements

214. Developer productivity, efficiency

215. Reliability

216. Classification – Overview What is measured? Is it measurable?

217. Classification of Software Metrics (In)dependency on the measurement context

219. McCabe's cyclomatic complexity

220. Code coverage with tests

222. Developer productivity

223. Source code comprehensibility

224. Usability

225. Classification – Overview What is measured? Is it measurable? Is context dependent?

226. Classification – Example What is measured? Is it measurable? Is context dependent?

229. http://www.stsc.hill.af.mil/crosstalk/1994/12/xt94d12b.asp

231. http://www.parlezuml.com/metrics/OO%20Design%20Principles%20&%20Metrics.pdf

232. http://www.parlezuml.com/metrics/Metrics%20Definitions.pdf

233. Home Reading David Longstreet “ Function Point Manual”

234. Thank you for your time and attention!