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