Posted by:
Amyjo
(
)
Date: January 07, 2016 12:17PM
Why do you lie about what the Pew says its statistical accuracy is? I don't know what you're trying to prove by lying.
They haven't admitted that, in fact they say they're very reliable.
"Q. How accurate are the statistics derived from Pew Research polls when applied to the population of the United States?
The accuracy of polls can be judged in different ways. One is the degree to which the sample of the public interviewed for the poll is representative of the whole population. For example, does the poll include the proper proportions of older and younger adults, of people of different races, or of men and women? Another standard for accuracy is whether the poll’s questions correctly measure the attitudes or relevant behaviors of the people who are interviewed. For both of these ways of judging accuracy, Pew Research’s polls do very well. We know that key characteristics of our samples conform closely to known population parameters from large government surveys such as the U.S. Census. ...
To improve the accuracy of our polls, we statistically adjust our samples so that they match the population in terms of the most important demographic characteristics such as education and region (see our detailed methodology statement for more about how this is done). This practice, called weighting, is commonly used in survey research."
http://www.pewresearch.org/2010/12/29/how-accurate-are-the-statistics-derived-from-pew-research-polls/"International migration is another factor that will influence the projected size of religious groups in various regions and countries.
Forecasting future migration patterns is difficult, because migration is often linked to government policies and international events that can change quickly. For this reason, many population projections do not include migration in their models. But working with researchers at the International Institute for Applied Systems Analysis in Laxenburg, Austria, the Pew Research Center has developed an innovative way of using data on past migration patterns to estimate the religious composition of migrant flows in the decades ahead....
The projections cover eight major groups: Buddhists, Christians, Hindus, Jews, Muslims, adherents of folk religions, adherents of other religions and the unaffiliated (see Appendix C: Defining the Religious Groups). Because censuses and surveys in many countries do not provide information on religious subgroups – such as Sunni and Shia Muslims or Catholic, Protestant and Orthodox Christians – the projections are for each religious group as a whole. Data on subgroups of the unaffiliated are also unavailable in many countries. As a result, separate projections are not possible for atheists or agnostics.
The projection model was developed in collaboration with researchers in the Age and Cohort Change Project at IIASA, who are world leaders in population projections methodology. The model uses an advanced version of the cohort-component method typically employed by demographers to forecast population growth. It starts with a population of baseline age groups, or cohorts, divided by sex and religion. Each cohort is projected into the future by adding likely gains (immigrants and people switching in) and by subtracting likely losses (deaths, emigrants and people switching out) year by year. The youngest cohorts, ages 0-4, are created by applying age-specific fertility rates to each female cohort in the childbearing years (ages 15-49), with children inheriting the mother’s religion. For more details, see the Methodology.12
In the process of gathering input data and developing the projection model, the Pew Research Center previously published reports on the current size and geographic distribution of major religious groups, including Muslims (2009), Christians (2011) and several other faiths (2012). An initial set of projections for one religious group, Muslims, was published in 2011, although it did not attempt to take religious switching into account.
Some social theorists have suggested that as countries develop economically, more of their inhabitants will move away from religious affiliation. While that has been the general experience in some parts of the world, notably Europe, it is not yet clear whether it is a universal pattern.13 In any case, the projections in this report are not based on theories about economic development leading to secularization.
Rather, the projections extend the recently observed patterns of religious switching in all countries for which sufficient data are available (70 countries in all). In addition, the projections reflect the United Nations’ expectation that in countries with high fertility rates, those rates gradually will decline in coming decades, alongside rising female educational attainment. And the projections assume that people gradually are living longer in most countries. These and other key input data and assumptions are explained in detail in Chapter 1 and the Methodology (Appendix A).
Since religious change has never previously been projected on this scale, some cautionary words are in order. Population projections are estimates built on current population data and assumptions about demographic trends, such as declining birth rates and rising life expectancies in particular countries. The projections are what will occur if the current data are accurate and current trends continue. But many events – scientific discoveries, armed conflicts, social movements, political upheavals, natural disasters and changing economic conditions, to name just a few – can shift demographic trends in unforeseen ways. That is why the projections are limited to a 40-year time frame, and subsequent chapters of this report try to give a sense of how much difference it could make if key assumptions were different.
For example, China’s 1.3 billion people (as of 2010) loom very large in global trends. At present, about 5% of China’s population is estimated to be Christian, and more than 50% is religiously unaffiliated. Because reliable figures on religious switching in China are not available, the projections do not contain any forecast for conversions in the world’s most populous country. But if Christianity expands in China in the decades to come – as some experts predict – then by 2050, the global numbers of Christians may be higher than projected, and the decline in the percentage of the world’s population that is religiously unaffiliated may be even sharper. (For more details on the possible impact of religious switching in China, see Chapter 1.)
Finally, readers should bear in mind that within every major religious group, there is a spectrum of belief and practice. The projections are based on the number of people who self-identify with each religious group, regardless of their level of observance. What it means to be Christian, Muslim, Hindu, Buddhist, Jewish or a member of any other faith may vary from person to person, country to country, and decade to decade."
http://www.pewforum.org/2015/04/02/religious-projections-2010-2050/