PSTAT FINAL EXAM QUESTIONS WITH
COMPLETE SOLUTIONS
68% |of |the |scores |that |lie |on |the |normal |curve |are |- |VERIFIED |ANSWER✔✔-between |1 |SD |above |and |
1 |SD |below |the |mean
A |z |score |designates |how |many |standard |deviations |the |raw |score |is |above |or |below |the |mean. |T/F |- |
VERIFIED |ANSWER✔✔-true
A |distribution |of |test |scores |is |positively |skewed. |Each |of |the |scores |is |converted |to |a |z |score. |The |
distribution |of |z |scores |is |- |VERIFIED |ANSWER✔✔-positively |skewed
Given |the |following |data |(4,5,7,9,12,15,18,20), |each |score |is |converted |to |a |z |score |and |then |the |
standard |deviation |of |the |z |scores |are |computed. |That |value |is |- |VERIFIED |ANSWER✔✔-1
A |z |score |is |- |VERIFIED |ANSWER✔✔-dependent |upon |the |mean |for |computation
Does |the |z |transformation |result |in |a |score |having |the |same |units |of |measurement |as |the |raw |score?
|- |VERIFIED |ANSWER✔✔-No. |The |z |scores |are |standard |scores |that |make |it |easier |to |compare |data
z |scores |- |VERIFIED |ANSWER✔✔-have |the |same |shape |as |the |set |of |raw |scores |from |which |they |were
|transformed
the |mean |of |z |scores |is |equal |to |0
the |standard |deviation |of |z |scores |is |equal |to |1
the |z |value |for |raw |scores |at |the |mean |= |- |VERIFIED |ANSWER✔✔-0
correlation |- |VERIFIED |ANSWER✔✔-highest |correlation |= |+/- |1
strong |correlation |= |.80+
medium |correlation |= |.60
, weak |correlation |= |.40
no |correlation |= |.00
scatter |plot |- |VERIFIED |ANSWER✔✔-a |graph |of |paired |x |and |y |values
can |be |both |linear |and |curvilinear
in |a |positive |relationship |- |VERIFIED |ANSWER✔✔-X |increases, |Y |increases
X |decreases, |Y |decreases
When |is |it |preferable |to |use |the |Spearman |rank |order |correlation? |- |VERIFIED |ANSWER✔✔-when |the |
data |are |of |ordinal |scaling
Qualities |of |Pearson |r |- |VERIFIED |ANSWER✔✔-X |is |cause |of |Y
the |correlation |is |an |accident |of |sampling
Y |is |the |cause |of |X
a |3rd |variable |is |the |cause |of |the |correlation |between |X |and |Y
a |correlation |between |college |entrance |exam |grades |and |scholastic |achievement |was |found |to |be |-
1.08. |On |the |basis |of |this, |you |would |conclude |that |- |VERIFIED |ANSWER✔✔-it |was |calculated |
incorrectly
Linear |relationships |- |VERIFIED |ANSWER✔✔-although |all |points |many |not |fall |on |the |line, |a |straight |
line |best |categorizes |the |relationship
a |linear |relationship |can |be |+/-
With |an |increase |in |the |value |for |the |standard |error |of |estimate, |our |confidence |in |the |prediction |of |
Y |given |x |- |VERIFIED |ANSWER✔✔-decreases
the |assumption |that |all |points |are |distributed |normally |around |the |regression |line |is |- |VERIFIED |
ANSWER✔✔-normality
COMPLETE SOLUTIONS
68% |of |the |scores |that |lie |on |the |normal |curve |are |- |VERIFIED |ANSWER✔✔-between |1 |SD |above |and |
1 |SD |below |the |mean
A |z |score |designates |how |many |standard |deviations |the |raw |score |is |above |or |below |the |mean. |T/F |- |
VERIFIED |ANSWER✔✔-true
A |distribution |of |test |scores |is |positively |skewed. |Each |of |the |scores |is |converted |to |a |z |score. |The |
distribution |of |z |scores |is |- |VERIFIED |ANSWER✔✔-positively |skewed
Given |the |following |data |(4,5,7,9,12,15,18,20), |each |score |is |converted |to |a |z |score |and |then |the |
standard |deviation |of |the |z |scores |are |computed. |That |value |is |- |VERIFIED |ANSWER✔✔-1
A |z |score |is |- |VERIFIED |ANSWER✔✔-dependent |upon |the |mean |for |computation
Does |the |z |transformation |result |in |a |score |having |the |same |units |of |measurement |as |the |raw |score?
|- |VERIFIED |ANSWER✔✔-No. |The |z |scores |are |standard |scores |that |make |it |easier |to |compare |data
z |scores |- |VERIFIED |ANSWER✔✔-have |the |same |shape |as |the |set |of |raw |scores |from |which |they |were
|transformed
the |mean |of |z |scores |is |equal |to |0
the |standard |deviation |of |z |scores |is |equal |to |1
the |z |value |for |raw |scores |at |the |mean |= |- |VERIFIED |ANSWER✔✔-0
correlation |- |VERIFIED |ANSWER✔✔-highest |correlation |= |+/- |1
strong |correlation |= |.80+
medium |correlation |= |.60
, weak |correlation |= |.40
no |correlation |= |.00
scatter |plot |- |VERIFIED |ANSWER✔✔-a |graph |of |paired |x |and |y |values
can |be |both |linear |and |curvilinear
in |a |positive |relationship |- |VERIFIED |ANSWER✔✔-X |increases, |Y |increases
X |decreases, |Y |decreases
When |is |it |preferable |to |use |the |Spearman |rank |order |correlation? |- |VERIFIED |ANSWER✔✔-when |the |
data |are |of |ordinal |scaling
Qualities |of |Pearson |r |- |VERIFIED |ANSWER✔✔-X |is |cause |of |Y
the |correlation |is |an |accident |of |sampling
Y |is |the |cause |of |X
a |3rd |variable |is |the |cause |of |the |correlation |between |X |and |Y
a |correlation |between |college |entrance |exam |grades |and |scholastic |achievement |was |found |to |be |-
1.08. |On |the |basis |of |this, |you |would |conclude |that |- |VERIFIED |ANSWER✔✔-it |was |calculated |
incorrectly
Linear |relationships |- |VERIFIED |ANSWER✔✔-although |all |points |many |not |fall |on |the |line, |a |straight |
line |best |categorizes |the |relationship
a |linear |relationship |can |be |+/-
With |an |increase |in |the |value |for |the |standard |error |of |estimate, |our |confidence |in |the |prediction |of |
Y |given |x |- |VERIFIED |ANSWER✔✔-decreases
the |assumption |that |all |points |are |distributed |normally |around |the |regression |line |is |- |VERIFIED |
ANSWER✔✔-normality
