STATS Chapter 7 Book
what are the 3 levels of confidence?
90, 95, 99
Which levels are preferred?
95 and 99
The highest level of confidence that is conventionally used with large samples is
99%
Why do researchers use samples rather than populations?
Because measuring an entire population is usually not only unfeasible but also unnecessary
_______ _______ _______: the fundamental, mathematical underpinning of confidence intervals
Central Limit Theorem
A ________ ________ (C.I.) is a type of probability statistic that specifies the range of values we use to estimate the location of an unknown population parameter such as a mean or a proportion
Confidence Interval
______ _______ are used to determine the probability that a given sample includes the population parameter (the population mean)
Confidence Interval
______ _______ provides us with a range of values within which the population parameter is likely to fall
Interval estimate
_______ ____ ________ (E) tells us how likely our parameter is to lie within that interval
Margin of Error
What determines the width of a C.I.?
Margin of error
A single statistic (usually a mean or percentage) that is used as our best estimate of a corresponding parameter--the value in a population from which you drew that estimate
Point Estimate
which estimate is more precise?
Point estimate
Another name for sampling error is _______ error
Random
_______ _______ tells us that the larger the sample size, the less the amount of sampling error we expect there to be----therefore a smaller margin of error
Sampling Theory
T/F As sample size increases, sampling error decreases
True
As confidence level increases, confidence interval _________
also increases
what determines interval width?
both n and the level of confidence
Levels of confidence, samples taken would do what (2)
capture the mean from the population and capture the proportion from the population
A ________ ________ specifies a range of values in which we estimate that a population parameter will fall
confidence interval
As sample size increases, the margin of error value will become smaller and the
confidence interval more narrow
A _______ _______ specifies the probability that the population parameter will indeed lie within that range
confidence level
A ________ _______ specifies the probability that our particular sample's interval estimate will in face contain the population parameter
confidence level
accuracy:
freedom from error
The ________ the level of confidence that we select, the wider the confidence interval will be
higher
Where do C.I. lie?
in the realm of inferential statistics
What reduced the margin of error?
increasing the sample size or repeating the samples over and over again
The higher the confidence level, the __________ risk
lower
The _______ ___ _______ (E) is an estimate of the amount of difference that we think is possible between our statistic and its corresponding parameter
margin of error
The lower the confidence level, the _________ risk that their interval estimate does not contain the parameter
more
Level of confidence refers to the probability that our interval estimate will contain the _________
parameter
While the main advantage of a point estimate is its ________, its main disadvantage is its __________
precision, inaccuracy
The gap is known as _______ ______
sampling error
Are point estimates complex or simple?
simple
A larger n will result in a _________ margin of error
smaller
What can the margin of error be defined as
the radius of the confidence interval
