1) An opinion poll was conducted by Pew Research Centre nationally between July 11 and July 15, 2018 regarding the merit of the increased tariffs being levied by US on various tradingpartners.Theresultsofthissurveycanbeobtainedfrom http://www.pollingreport.com/trade.htm The poll question is indicated follows. “Overall, do you think these increased tariffs between the U.S. and its trading partners will be good or bad for the United States?" 2) The results of the survey are summarised as below. 40% of the respondents opined that the tariffs applied by the US on the trading partners will be good for USA. 49% of the respondents opined that the tariffs applied by the US on the trading partners will be bad for USA. 11% of the respondents were unsure of their opinion on the impact of the tariffs imposed on the trading partners for USA. 3) The obtaining of the requisite confidence interval can be facilitated by adding and subtracting the margin of error. Thus, confidence interval for proportion of people who are in favour of tariffs on other trading partners would be (40%-3.7%, 40%+3.7%) i.e. (36.3%, 43.7%). It may be estimated that the average proportion of population who is in favour of levying of tariffs on the trading partners would lie between 36.3% and 43.7% (Flick, 2015). 4) The confidence interval can be computed using the given data for the sample. Mean proportion of those who are in favour = 0.40
Sample size = 1007 Standard error = √((0.4)*(1-0.4)/1007) = 0.0154 Since the confidence level is 95%, hence the z level corresponding to this confidence level would be 1.959 (Hillier, 2016). Thus, lower level of 95% confidence interval = 0.4 -1.959*0.0154 = 0.3697 or 36.97% Upper level of 95% confidence interval = 0.4 + 1.959*0.0154 = 0. 43.03% 5) The calculated confidence interval is (36.97%, 43.03%). This is slightly different from the confidence interval which has been derived based on the poll data margin of error. The potential difference between the two values can be on account of the presence of potential biases (Eriksson & Kovalainen, 2015). 6) The given study might be influenced by a host of biases which need to be indicated. One of the first ones would be the selection bias which relates to the process involved in obtaining the sample which may have led to a sample which is not representative of the underlying population of interest. Additionally, the underlying sampling technique is not known which can also potentially be a source of bias since the key attributes of the population may not be well represented in the sample. Additionally, the orientation of the sponsoring authority may have influenced the underlying methods deployed and may be the result in order to serve vested interests which may have also introduced bias in the results obtained from the survey (Hair, Wolfinbarger, Money, Samouel & Page, 2015).
References Eriksson, P. & Kovalainen, A. (2015)Quantitative methods in business research. 3rd ed. London: Sage Publications. Flick, U. (2015)Introducing research methodology: A beginner's guide to doing a research project.4th ed. New York: Sage Publications Hair, J. F., Wolfinbarger, M., Money, A. H., Samouel, P., & Page, M. J. (2015)Essentials of business research methods.2nd ed. New York: Routledge. Hillier, F. (2016)Introduction to Operations Research.6th ed.New York: McGraw Hill Publications.