BUS 308 Week 2 Quiz (All correct)

BUS 308 Statistics for Managers (DCH1433A)

Week 2 Quiz (All correct)

Question 1                         

The mean of the distribution of sample means will have the same value as the mean of the distribution of individual scores upon which it is based.

True

False

Question 2                         

Why do the critical values change with degrees of freedom for the t-tests?

@Answer found in section 4.3 The One-sample t-Test, in Statistics for Managers

Different degrees of freedom define different t distributions

Because the critical values are calculated directly from degrees of freedom

The degrees of freedom reflect the value of SEM.

The degrees of freedom are indexed to the M – μM difference.

Question 3

The desired sample depends on all of these factors except?

@Answer found in section 3.4, in Statistics for Managers

The desired certainty of results, expressed as a z score

The variance in the data set

 The allowable error or variation from the actual population mean

The size of the population to be sampled

Question 4                         

What question does the z test answer?

Is the individual characteristic of the group?

 Has there been a type I error?

 Does the sample represent the population?

Are the data normal?

Question 5

Statistical significance for a tested mean difference means practical significance as well.

True

 False

 Question 6.                      

According to the central limit theorem, a population which is skewed to begin with will still be skewed when it is re-formed as a distribution of sample means.

True

False

Question 7

The standard error of the mean is actually the standard deviation of all of the means that make up the distribution of sample means.

True

False

Question 8                         

Large differences in the numerator of a statistical test for differences for means are the only critical factor in determining statistical significance.

True

  False

Question 9                         

What is the relationship between the power of a statistical test and decision errors?

@Answer found in section 4.3 The One-sample t-Test, in Statistics for Managers

 Powerful tests minimize the risk of decision errors.

Powerful tests are more inclined to type II than type I errors.

Powerful tests compensate for decision errors with stronger effect sizes.

Powerful tests minimize type II errors.

Question 10.                     

The independent t-test is based on which distribution?

@Answer found in section 4.5 The Independent Samples t-Test, in Statistics for Managers

 The distribution of difference scores

The distribution of sample means

The distribution of error scores

 The distribution of z