Question

	Number of People Making Contribution
Ethnic Group	$1-50	$51-100	$101-150	$151-200	Over $200	Row Total
A	82	64	45	38	22	251
B	91	54	67	30	22	264
C	74	68	59	35	30	266
D	98	87	71	54	30	340
Column Total	345	273	242	157	104	1121

(b) Find the value of the chi-square statistic for the sample. (Round the expected frequencies to at least three decimal places. Round the test statistic to three decimal places.)

Answer 1

Ethnic group	$1-50	$51-100	$101-150	$151-200	Over $200	Row Total
A	82	64	45	38	22	251
B	91	54	67	30	22	264
C	74	68	59	35	30	266
D	98	87	71	54	30	340
Column Total	345	273	242	157	104	1121

The test statistic is

O: Observed frequency
E: Expected frequency.
E = ( Row total*Column total) / Grand total

O	E	(O-E)	(O-E)^2	(O-E)^2/E
82	77.24799	4.752007	22.58157	0.292326
64	61.12667	2.873327	8.25601	0.135064
45	54.18555	-9.18555	84.3743	1.557137
38	35.15343	2.846566	8.102936	0.230502
22	23.28635	-1.28635	1.6547	0.071059
91	81.24888	9.751115	95.08425	1.170284
54	64.2926	-10.2926	105.9375	1.647741
67	56.99197	10.00803	100.1606	1.757452
30	36.97413	-6.97413	48.63849	1.315474
22	24.49242	-2.49242	6.212145	0.253635
74	81.86441	-7.86441	61.84889	0.755504
68	64.77966	3.220339	10.37058	0.16009
59	57.42373	1.576271	2.484631	0.043268
35	37.25424	-2.25424	5.081586	0.136403
30	24.67797	5.322034	28.32404	1.147746
98	104.6387	-6.63872	44.07254	0.421188
87	82.80107	4.19893	17.63101	0.212932
71	73.39875	-2.39875	5.754007	0.078394
54	47.6182	6.381802	40.7274	0.855291
30	31.54326	-1.54326	2.381667	0.075505
			Total	12.317