Question

The economic dynamism, which is the index of productive growth in dollars for countries that are designated by the World Bank as middle-income are in table #8.3.9 ("SOCR data 2008," 2013). Compute a 95% confidence interval for the mean economic dynamism of middle-income countries.

Table #8.3.9: Economic Dynamism ($) of Middle Income Countries

25.8057	37.4511	51.915	43.6952	47.8506	43.7178	58.0767
41.1648	38.0793	37.7251	39.6553	42.0265	48.6159	43.8555
49.1361	61.9281	41.9543	44.9346	46.0521	48.3652	43.6252
50.9866	59.1724	39.6282	33.6074	21.6643

Answer 1

The 95% confidence interval for the mean economic dynamism of middle-income countries is obtained using the following formula,

(SInce the population standard deviation is not known t critical value is used)

For the calculation purposes, the sample mean and sample standard deviation values is obtained in excel

The t critical value is obtained for the significance level = 0.05 and degree of freedom = n -1 = 26 - 1 = 25.