STAT 121 Test Questions Verified Answers
How is level of confidence determined?
Subjectively determined by the researcher.
Level of confidence can be defined as
the percentage of the time that the procedure will produce intervals that contains
the parameter value.
Margin of error for 99% confidence tells us
the most a statistic differs from the parameter for the middle 99% of all
possible statistic values.
A test of significance is intended to assess
the evidence provided by data against the null hypothesis in favor of the
alternative hypothesis.
What is the purpose of a confidence interval?
to estimate the value of a parameter
Which one of the following is NOT a correct statement about margin of error?
For fixed sample size, decreasing level of confidence increases the margin of error.
If we decrease our level of confidence, keeping all else constant, our margin of error will
Decrease
, All of the following are true statements about the P-value except one. Which statement
is false?
a) P-value is the area in the tail of the sampling distribution defined by H0.
b) The smaller the P-value, the greater the evidence for the alternative hypothesis.
c) The larger the P-value, the greater the agreement between the data and H0.
d) P-value is used to determine the significance level.
d) P-value is used to determine the significance level.
Tests of significance on μ and confidence intervals for μ (with σ known) are based on
the sampling distribution of x.̄
The shape of the t-distribution gets closer and closer to the shape of standard
Normal distribution as the degrees of freedom increase.
True
Power is the probability that Ha is believed when H0 is true.
False
α is found in the fail to reject H0 region under the curve of the sampling distribution defined
by H0.
False
For fixed α, increasing sample size increases power.
True
The margin of error for a 90% confidence interval is larger than the margin of error for a
99% confidence interval (all other things being equal.)
False
One Sample t Procedure
How is level of confidence determined?
Subjectively determined by the researcher.
Level of confidence can be defined as
the percentage of the time that the procedure will produce intervals that contains
the parameter value.
Margin of error for 99% confidence tells us
the most a statistic differs from the parameter for the middle 99% of all
possible statistic values.
A test of significance is intended to assess
the evidence provided by data against the null hypothesis in favor of the
alternative hypothesis.
What is the purpose of a confidence interval?
to estimate the value of a parameter
Which one of the following is NOT a correct statement about margin of error?
For fixed sample size, decreasing level of confidence increases the margin of error.
If we decrease our level of confidence, keeping all else constant, our margin of error will
Decrease
, All of the following are true statements about the P-value except one. Which statement
is false?
a) P-value is the area in the tail of the sampling distribution defined by H0.
b) The smaller the P-value, the greater the evidence for the alternative hypothesis.
c) The larger the P-value, the greater the agreement between the data and H0.
d) P-value is used to determine the significance level.
d) P-value is used to determine the significance level.
Tests of significance on μ and confidence intervals for μ (with σ known) are based on
the sampling distribution of x.̄
The shape of the t-distribution gets closer and closer to the shape of standard
Normal distribution as the degrees of freedom increase.
True
Power is the probability that Ha is believed when H0 is true.
False
α is found in the fail to reject H0 region under the curve of the sampling distribution defined
by H0.
False
For fixed α, increasing sample size increases power.
True
The margin of error for a 90% confidence interval is larger than the margin of error for a
99% confidence interval (all other things being equal.)
False
One Sample t Procedure
