Understanding Contributor to Developer Turnover Patterns in OSS Projects: A Case Study of Apache Projects

Table 4

Yearly average contribution ratio of a potential developer before and after attaining the role of a developer.

Variable	Mean		St. Dev
	Before	After	Before	After
Apache Ant (n = 13)
bugs reported	17.23	2.35	17.98	3.65
bug comments	41.44	39.02	37.66	34.83
bug social relation	44.65	31.57	51.41	23.34
emails	230.49	280.34	259	224.52
email social relation	30.5	20.31	30.35	13.55
Apache Lucene (n = 22)
bugs reported	14.12	23.73	9.12	32.74
bug comments	24.84	73.21	18.18	91.85
bug social relation	33.57	34.67	23.75	30.02
emails	130	398.71	124.87	508.02
email social relation	19.59	21.69	16.53	15.32
Apache Maven (n = 21)
bugs reported	28.40	27.82	53.27	79.49
bug comments	16.42	27.86	12.07	58.68
bug social relation	27.16	24.08	21.43	30.85
emails	158.41	185.55	218.27	174.89
email social relation	18.33	23.34	18.31	15.73
Apache Solr (n = 13)
bugs reported	24.77	23.75	30.38	17.50
bug comments	44.72	84.77	41.35	86.25
bug social relation	68.04	80.46	52.18	52.39
emails	156.01	313.82	227.57	333.19
email social relation	14.72	38.47	7.85	33.04