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What else can I help you with?
What did the 1936 election demonstrate that a good poll needed?
The election of 1948 demonstrated that a good poll needed a later sample.
What is needed to have good poll?
random sample
Can increasing sample size reduce random error?
Random error and sample size have an inverse relationship...As sample size INCREASES random error DECREASES. There's a good explanation at the related link.
Why is the opinion of the public about a popular movie or television program not a good example of public opinion?
why is the opinion of the public about a popular movie or television program not a good example of public opinion?
What distinguishes a probability sample from a non probability sample?
I believe you meant to ask: What distinguishes a random sample from a non random sample? A random sample means the selection or sampling from the population is by chance. Looking at the data, one might not be able to tell if the sample is random or selective. Consider a marketing survey which is included everytime you buy an item online. Random or non-random? It is a survey of recent customers, and probably a pretty good one. But it is not a random selection of all customers who have made purchases with clients.
A way to collect survey data?
A simple random sample is good!
What is the problem of random sampling?
With random sampling, you are hoping to get a representative sample of a whole, however statistically you could get a sample that is very different from the whole it was selected from. The larger the sample proportion of the whole, the better your sample will be. For example, a sample of 10 out of 100 is not as good as 20 out of 100. The bigger the sample the closer to the actual whole average you will get.
How does public opinion effect a candidate seeking political office?
If the candidate doesn't have good public opinion, chances are the public won't vote for him or her and they won't get elected.
How is it that a random samples gives a fairly accurate representation of public opinion?
The main point here is that the Sample Mean can be used to estimate the Population Mean. What I mean by that is that on average, the Sample Mean is a good estimator of the Population Mean. There are two reasons for this, the first is that the Bias of the estimator, in this case the Sample Mean, is zero. A Bias other than zero overestimates or underestimates the Population Mean depending on its value. Bias = Expected value of estimator - mean. This can be expressed as EX(pheta) - mu (pheta) As the Sample Mean has an expected value (what value it expects to take on average) of itself then the greek letter mu which stands for the Sample Mean will provide a Bias of 0. Bias = mu - mu = 0 Secondly as the Variance of the the Sample Mean is mu/(n-1) this leads us to believe that the Variance will fall as we increase the sample size. Variance is a measure of the dispersion of values collected from the centre of the data. Where the centre of the data is a fixed value equal to the median. Put Bias and Variance together and you get the Mean Squared Error which is the error associated with using an estimator of the Population Mean. The formula for Mean Squared Error = Bias^2 + Variance With our estimator we can see that as the Bias = zero, it has no relevance to the error and as the variance falls as the sample size increases then we can conclude that the error associated with using the sample mean will fall as the sample size increases. Conclusions: The Random Sample of public opinon will on average lead to a true representation of the Population Mean and therefore the random samle you have will represnt the public opinion to a fairly high degree of accuracy. Finally, this degree of accuracy will rise incredibly quickly as the sample size rises thus leading to a very accurate representation (on average)
What is a random sample?
A random sample is a selection from the population of interest where each item (persons, households, widgets, etc.) has an equal chance of being selected. The idea being that measuring a random sample of sufficient size will accurately (within a margin of error) reflect the "true" value that exists in the population - while at the same time reducing your study to a manageable size. A random sample is integral in good survey design to reduce bias in your experiment.
Match each type of good with the sample good it represents (apex)?
Merit good : education Public good : national security Individual good : food
What kind of good is an education in a public school?
in my opinion public schools really are not any worse than private schools. as long as the public school has a good reputation a person can learn just as much as in a private school.
