Ana Ligthart, I6299483
Assignments
WEEK4 - Seminar 4.2
All relevant statistical concepts have been discussed earlier, but repeating the
discussion of several concepts is always good.
In this seminar regression analysis is combined with statistical testing and the results of a t-
test are compared with that of a regression analysis.
Question 1
The p-value as obtained in the chi-square test for a contingency table expresses:
a. how likely it is to obtain the observed chi-square value or an even larger value if there
is no relation between the row and column variable
b. how likely it is to obtain the observed chi-square value or an even smaller value if
there is no relation between the row and column variable
c. how likely it is to obtain the observed chi-square value or an even larger value if there
is a relation between the row and column variable
d. how likely it is to obtain the observed chi-square value or an even smaller value if
there is a relation between the row and column variable
De nulhypothese gaat er van uit dat X en Y onafhankelijk zijn van elkaar.
Question 2
If the p-value of the chi-square test for a contingency table is below the significance level α ,
what can be concluded?
a. the data indicate that the row and column variables are directly (positively) related
b. the data indicate that the row and column variables are not related
c. the data indicate that the row and column variables are related
d. the data indicate that the row and column variables are reversely (negatively) related
De p-value zegt niets over de soort relatie tussen de variabelen.
, Question 3
Suppose the p-value of the chi-square test for a 2 ×2 contingency table is below the
significance level α =0.10 . Which interpretation is most correct?
a. there is enough counterevidence against the null hypothesis
b. there is enough counterevidence against the alternative hypothesis
c. the probability of the null hypothesis being true is below 10 %
d. the probability of the alternative hypothesis being true is below 10 %
Er is geen 10% kans dat de nulhypothese correct is, maar er is 10% kans dat de
nulhypothese wordt verworpen terwijl deze eigenlijk correct is (=type I error).
Question 4
Suppose we perform an experiment into the effect of biofeedback (Yes or No) on a person’s
blood pressure (too high or not). What assumption is made in case the data of the resulting
contingency table are analyzed by a chi-square test?
a. the variable blood pressure should be of at least interval scale level
b. the error score of the variable blood pressure should be normally distributed
c. persons are measured either under the condition of biofeedback or under the
condition of no biofeedback, but not under both conditions
d. there is a relation between a person’s blood pressure and being trained in biofeedback
or not
De variabelen kunnen ook categorisch zijn (A), de tweede assumptie gaat over lineaire
regressie (B), maar bij een chi-square test wordt juist uitgegaan van géén relatie tussen de
variabelen, dus D is fout.
Question 5
Consider the study described in problem 11 of seminar 2.1 (week 2, seminar1). The study
investigates the relation between feeling to collapse and marital status. Consult the SPSS
output created in problem 12of that seminar. Take a significance level α =0.05 and answer
the following questions:
a. What is the null hypothesis that is tested with the chi-square test?
H0: μ(collapse∨married )=μ(collapse ∨unmarried )
b. What is the alternative hypothesis?
H1: μ(collapse∨married ) ≠ μ(collapse ∨unmarried )
c. What is the p-value for this test? Does this provide evidence against the null
hypothesis? Explain your answer.
De p-value is 0.003. Dit is kleiner dan 0.05 dus de H0 wordt verworpen.
Assignments
WEEK4 - Seminar 4.2
All relevant statistical concepts have been discussed earlier, but repeating the
discussion of several concepts is always good.
In this seminar regression analysis is combined with statistical testing and the results of a t-
test are compared with that of a regression analysis.
Question 1
The p-value as obtained in the chi-square test for a contingency table expresses:
a. how likely it is to obtain the observed chi-square value or an even larger value if there
is no relation between the row and column variable
b. how likely it is to obtain the observed chi-square value or an even smaller value if
there is no relation between the row and column variable
c. how likely it is to obtain the observed chi-square value or an even larger value if there
is a relation between the row and column variable
d. how likely it is to obtain the observed chi-square value or an even smaller value if
there is a relation between the row and column variable
De nulhypothese gaat er van uit dat X en Y onafhankelijk zijn van elkaar.
Question 2
If the p-value of the chi-square test for a contingency table is below the significance level α ,
what can be concluded?
a. the data indicate that the row and column variables are directly (positively) related
b. the data indicate that the row and column variables are not related
c. the data indicate that the row and column variables are related
d. the data indicate that the row and column variables are reversely (negatively) related
De p-value zegt niets over de soort relatie tussen de variabelen.
, Question 3
Suppose the p-value of the chi-square test for a 2 ×2 contingency table is below the
significance level α =0.10 . Which interpretation is most correct?
a. there is enough counterevidence against the null hypothesis
b. there is enough counterevidence against the alternative hypothesis
c. the probability of the null hypothesis being true is below 10 %
d. the probability of the alternative hypothesis being true is below 10 %
Er is geen 10% kans dat de nulhypothese correct is, maar er is 10% kans dat de
nulhypothese wordt verworpen terwijl deze eigenlijk correct is (=type I error).
Question 4
Suppose we perform an experiment into the effect of biofeedback (Yes or No) on a person’s
blood pressure (too high or not). What assumption is made in case the data of the resulting
contingency table are analyzed by a chi-square test?
a. the variable blood pressure should be of at least interval scale level
b. the error score of the variable blood pressure should be normally distributed
c. persons are measured either under the condition of biofeedback or under the
condition of no biofeedback, but not under both conditions
d. there is a relation between a person’s blood pressure and being trained in biofeedback
or not
De variabelen kunnen ook categorisch zijn (A), de tweede assumptie gaat over lineaire
regressie (B), maar bij een chi-square test wordt juist uitgegaan van géén relatie tussen de
variabelen, dus D is fout.
Question 5
Consider the study described in problem 11 of seminar 2.1 (week 2, seminar1). The study
investigates the relation between feeling to collapse and marital status. Consult the SPSS
output created in problem 12of that seminar. Take a significance level α =0.05 and answer
the following questions:
a. What is the null hypothesis that is tested with the chi-square test?
H0: μ(collapse∨married )=μ(collapse ∨unmarried )
b. What is the alternative hypothesis?
H1: μ(collapse∨married ) ≠ μ(collapse ∨unmarried )
c. What is the p-value for this test? Does this provide evidence against the null
hypothesis? Explain your answer.
De p-value is 0.003. Dit is kleiner dan 0.05 dus de H0 wordt verworpen.
