what is the probability of winning the world series when the team gets the first victory of the series

The Boston Americans had 1 win in the 1903 World Series.

Interpreted as:

What is the probability of winning the world series when the team gets the first victory in a season of the series?

	TEAM	SERIES W	W	SEASON	SERIES	L	W%	G	AB	R	H	2B	3B	HR	RBI	BB	HBP	SO	SB	CS	PA	TB	XBH	SH	IBB	GIDP	AVG	OBP	SLG	OPS
1	Americans	1	5	1903	World Series	3	.625	8	281	39	69	4	16	2	34	14	3	29	5	2	304	111	22	6	0	4	.246	.289	.395	.684
2	Giants	1	4	1905	World Series	1	.800	5	153	15	33	7	0	0	13	15	2	26	11	5	175	40	7	5	2	1	.216	.294	.261	.556
3	White Sox	1	4	1906	World Series	2	.667	6	187	22	37	10	3	0	19	18	3	35	6	6	214	53	13	6	0	1	.198	.279	.283	.562
4	Cubs	1	4	1907	World Series	0	1.000	5	166	19	42	6	1	0	15	13	4	26	16	5	192	50	7	9	0	0	.253	.322	.301	.624
5	Cubs	1	4	1908	World Series	1	.800	5	164	24	48	4	2	1	20	13	0	26	15	8	185	59	7	8	0	3	.293	.345	.360	.704
6	Pirates	1	4	1909	World Series	3	.571	7	223	34	50	13	1	2	25	20	6	34	18	6	258	71	16	9	0	0	.224	.305	.318	.624
7	Athletics	1	4	1910	World Series	1	.800	5	177	35	57	19	2	1	30	17	2	24	7	7	203	83	22	7	0	3	.322	.388	.469	.857
8	Athletics	1	4	1911	World Series	2	.667	6	205	27	50	15	0	3	21	4	0	31	4	6	216	74	18	7	1	0	.244	.258	.361	.619
9	Red Sox	1	4	1912	World Series	3	.571	8	273	25	60	14	6	1	21	19	1	36	5	3	299	89	21	6	1	2	.220	.273	.326	.599
10	Athletics	1	4	1913	World Series	1	.800	5	174	23	46	4	4	2	21	7	0	16	5	1	186	64	10	5	1	0	.264	.293	.368	.661
11	Braves	1	4	1914	World Series	0	1.000	4	135	16	33	6	2	1	14	15	1	18	9	3	153	46	9	2	1	3	.244	.325	.341	.665
12	Red Sox	1	4	1915	World Series	1	.800	5	159	12	42	2	2	3	11	11	1	25	1	6	177	57	7	6	1	3	.264	.316	.358	.674
13	Red Sox	1	4	1916	World Series	1	.800	5	164	21	39	7	6	2	18	18	0	25	1	6	192	64	15	10	1	1	.238	.313	.390	.703
14	White Sox	1	4	1917	World Series	2	.667	6	197	21	54	6	0	1	18	11	0	28	6	8	211	63	7	3	0	1	.274	.313	.320	.632
15	Red Sox	1	4	1918	World Series	2	.667	6	172	9	32	2	3	0	6	16	1	21	3	3	197	40	5	8	1	3	.186	.259	.233	.492
16	Reds	1	5	1919	World Series	3	.625	8	251	35	64	10	7	0	34	25	5	22	7	10	292	88	17	11	0	4	.255	.335	.351	.685
17	Indians	1	5	1920	World Series	2	.714	7	217	21	53	9	2	2	18	21	0	21	2	6	240	72	13	2	3	3	.244	.311	.332	.643
18	Giants	1	5	1921	World Series	3	.625	8	264	29	71	13	4	2	28	22	1	38	7	9	292	98	19	5	0	4	.269	.328	.371	.699
19	Giants	1	4	1922	World Series	0	1.000	5	162	18	50	2	1	1	18	12	0	15	1	3	177	57	4	3	1	6	.309	.356	.352	.708
20	Yankees	1	4	1923	World Series	2	.667	6	205	30	60	8	4	5	28	20	1	22	1	0	230	91	17	4	0	5	.293	.358	.444	.802
21	Senators	1	4	1924	World Series	3	.571	7	248	26	61	9	0	5	25	29	0	34	5	4	282	85	14	5	2	4	.246	.325	.343	.668
22	Pirates	1	4	1925	World Series	3	.571	7	230	25	61	12	2	4	25	17	4	32	7	2	257	89	18	6	1	6	.265	.327	.387	.714
23	Cardinals	1	4	1926	World Series	3	.571	7	239	31	65	12	1	4	30	11	1	30	2	4	260	91	17	9	0	3	.272	.307	.381	.688
24	Yankees	1	4	1927	World Series	0	1.000	4	136	23	38	6	2	2	19	13	1	25	2	0	152	54	10	2	1	2	.279	.347	.397	.744
25	Yankees	1	4	1928	World Series	0	1.000	4	134	27	37	7	0	9	25	13	1	13	4	0	151	71	16	3	0	3	.276	.345	.530	.874