Medical tests were conducted to learn about drug-resistant tuberculosis. of 142 cases tested in new jersey, 9 were found to be d
rug-resistant. of 268 cases tested in texas, 5 were found to be drug-resistant. do these data suggest a statistically significant difference between the proportions of drug-resistant cases in the two states? use a.02 level of significance. hint: make sure that you carry 4 decimals for your intermediate workings.
Phat1 = 9/142 Phat 2 = 5/268 Phat 3 14/410 Test statistics = (Phat 1 - Phat 2) / (Square root of (phat × (1- phat)) times the square root of (1/n1 + 1/n2)) Test statistics = 2.373 P- value = 2× (1- normal cdf (2.373, 0, 1)) = 0.0176 At the level of significance, there is difference between the proportion of drug-resistant wihtin the two states.
A climax community (Figure below) is the end result of ecological succession. The climax community is a stable balance of all organisms in an ecosystem and will remain stable unless a disaster strikes. After the disaster, succession will start all over again.
The node therefore represents the end of the ancestral taxon and the stems , the species that split from the ancestor. The two taxa that split from the node are called sister taxa.
