Statistics Chapter 9: Estimation and Confidence Interval

Stats chapter 9 

29 cards   |   Total Attempts: 183
  

Cards In This Set

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Point estimate
Single statistic used to estimate a populatoin parameter
What is the point estimate of the mean of a population
Mean of a sample
What is the point estimate of population propotion (pie)
P, sample proportion
What is the point estimate of a population standard deviation?
Sample standard deviation
Confidence interval measures
How close the point estimate is to the population parameter
Confidence interval
A range of values constructed from sample data that the population parameter is likely to occur wihtin that range at a specified probability. the specified prob is called the level of confidence
95% of the sample means are within what of what?
1.96 standard deviations of the population mean
The standard deviations discussed are called
Sampling errors, because they are the standard deviation of sampling means.
95% confidence intervals only leaves __% and that is devided into what?
5% and is devided into half for each tail
What does the t distribution handle?
Unknown standard devation
What is the shape of a t?
Flatter then a noraml dis. more spread out
Why is t dis like this?
Because it has a larger standard deviation then the normal dis
What kind of a distribution is a t?
Continuous
What is the shape of a t?
Bell shaped and symmetrical
What grouping is a t?
Into families of t distributions