Have you ever been disappointed because a television network cancelled one of yo
ID: 2727855 • Letter: H
Question
Have you ever been disappointed because a television network cancelled one of your favorite television shows because of “low ratings”? The network didn’t ask your opinion, did it? It probably didn’t ask any of your friends, either. That’s because estimates of television audience sizes are based on research done by The Nielsen Company, which uses a sample of only 9,000 households out of the more than 113 million households in the United States to determine national ratings for television programs. That doesn’t seem like enough, does it? As it turns out, statistically, it’s many more than enough.After reading this, go to 4.1. and 4.2. shown below.
4.1. Go to www.surveysystem.com/sscalc.htm to determine the appropriate sample size for a population of 113 million households. Assuming a confidence interval of 5, how large should the sample of households be if desiring a 95-percent confidence level? How large for a 99-percent confidence level? Briefly explain what is meant by confidence interval and confidence level.
4.2. What sample sizes are necessary at population sizes of 1 billion, 10,000, and 100 with a confidence interval of 5 and a 95-percent confidence level? Explain the effect population size has on sample size.
Explanation / Answer
4.1
he confidence interval (also called margin of error) is the plus-or-minus figure usually reported in newspaper or television opinion poll results. For example, if you use a confidence interval of 4 and 47% percent of your sample picks an answer you can be "sure" that if you had asked the question of the entire relevant population between 43% (47-4) and 51% (47+4) would have picked that answer.
The confidence level tells you how sure you can be. It is expressed as a percentage and represents how often the true percentage of the population who would pick an answer lies within the confidence interval. The 95% confidence level means you can be 95% certain; the 99% confidence level means you can be 99% certain. Most researchers use the 95% confidence level.
4.2
The population size does matter, but, unless the sample size is a large proportion of the population, it matters so little that it can be ignored. For little differences in population the sample size doesnot change but for huge differences in population, the sample size also changes.
Population Confidence Interval Confidence Level Appropriate Sample Size 113000000 5 95 384 113000000 5 99 666Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.