Module 5: The t-Test CORRECT 100%
When population standard deviation is known, the z-score is used, when population
standard deviation is unknown, the __ is used - ANSWERt-score
True/False
Since t-scores are centered normally around the mean and form a bell-shaped
curve, probabilities can be calculated to draw inferences about populations. -
ANSWERTrue
___ determine how well the t-distribution approximates the normal distribution of the
z-scores. To calculate for any sample size, n-1 - ANSWERDegrees of freedom (df)
A t distribution approximately resembles a normal distribution when n=___ -
ANSWERn=12
T-testing for a one sample test is used when __ - ANSWERthe population mean is
known
I A larger sample size ___ standard error which reduces margin of error -
ANSWERreduces
A 95% confidence interval tells a researcher __ - ANSWERA 95% confidence
interval tells a researcher that they can be 95% confidence that the true population
mean falls between the lower end -> higher end.
n a one sample test, state the possible Ho and Ha hypotheses - ANSWERHo:
µ = known population mean
Ha:
µ > known population mean (right tailed)
µ < known population mean (left tailed)
µ ≠ equal known population mean (two tailed)
How to calculate df for one sample tests - ANSWERn-1
For t-testing, you compute ___ based on a sample statistic rather than using a
standard deviation based on a population parameter - ANSWERstandard error
The __ is centered around the mean, extending to the left and to the right to include
estimated standard error, sx̄. It provides a range of values that would likely contain
the population mean at a given alpha level. - ANSWERconfidence intervals
To increase the range of a confidence interval, ____ - ANSWERdecrease the
significance level
A 95% confidence intervals between -0.002 and 0.9205 is reported in research as: -
ANSWER95% CI [-0.002, 0.9205]
When population standard deviation is known, the z-score is used, when population
standard deviation is unknown, the __ is used - ANSWERt-score
True/False
Since t-scores are centered normally around the mean and form a bell-shaped
curve, probabilities can be calculated to draw inferences about populations. -
ANSWERTrue
___ determine how well the t-distribution approximates the normal distribution of the
z-scores. To calculate for any sample size, n-1 - ANSWERDegrees of freedom (df)
A t distribution approximately resembles a normal distribution when n=___ -
ANSWERn=12
T-testing for a one sample test is used when __ - ANSWERthe population mean is
known
I A larger sample size ___ standard error which reduces margin of error -
ANSWERreduces
A 95% confidence interval tells a researcher __ - ANSWERA 95% confidence
interval tells a researcher that they can be 95% confidence that the true population
mean falls between the lower end -> higher end.
n a one sample test, state the possible Ho and Ha hypotheses - ANSWERHo:
µ = known population mean
Ha:
µ > known population mean (right tailed)
µ < known population mean (left tailed)
µ ≠ equal known population mean (two tailed)
How to calculate df for one sample tests - ANSWERn-1
For t-testing, you compute ___ based on a sample statistic rather than using a
standard deviation based on a population parameter - ANSWERstandard error
The __ is centered around the mean, extending to the left and to the right to include
estimated standard error, sx̄. It provides a range of values that would likely contain
the population mean at a given alpha level. - ANSWERconfidence intervals
To increase the range of a confidence interval, ____ - ANSWERdecrease the
significance level
A 95% confidence intervals between -0.002 and 0.9205 is reported in research as: -
ANSWER95% CI [-0.002, 0.9205]
