MCQ Flashcards
If SD is 5, the variance is what?
25
Positive kurtosis (leptokurtic) indicates what?
Scores are tightly clustered around the centre of the distribution
mean = 28, SD = 3, the z-score for a score of 34 is what?
2
An assumption for a one way repeated measures ANOVA but not a one way independent ANOVA
Sphericity
a p-value of 0.002 tells you what?
The probability of getting this result by chance is 0.2%, assuming the null hypothesis is correct
out of the following, which is the most appropriate reason to use a non-parametric test?:
A When the DV is measured on an ordinal scale
B When you have unequal sample sizes between conditions of the IV
C When the sample size is small
D When you have a violation of the assumption of homogeneity of variance
A
The following are all commonly stated assumptions/requirements for using ANOVA. Which of the 4 is the only one that the procedure always requires?
A Subjects are assigned to treatment conditions / groups using random allocation
B Data is from a normally distributed population
C DV is continuous (interval or ratio)
D Variance in each experimental condition is similar (assumption of homogeneity of variance)
C
A researcher runs a single t test and obtains a p value of p = .04. The researcher rejects the null hypothesis and concludes that there is a significant effect of the experimental manipulation in the population. What error or errors have they possibly made?
The researcher may have made a type 1 error
99% of z-scores lie between what:
+/- 2.58
If predictor X shows a correlation coefficient of -.45 with outcome Y, we can confidently say that:
A X is a significant predictor of Y
B Variance in X accounts for 20.25% (that’s -.45²) of the variance in Y
C X has a causal relationship with Y
D All of the above
B
How much variance has been explained by a correlation of r = .50?
25%
The relationship between two variables partialling out the effect that a third variable has on both of those variables can be expressed using what?
Partial correlation
A regression model in which variables are entered into the model on the basis of a mathematical criterion is known as a:
Stepwise regression
In multiple regression, a high VIF statistic, a low tolerance statistic, and substantial correlations between predictor variables, ALL indicate what?
Multicollinearity
In a multiple regression model, the t test statistic can be used to test?
The significance of the regression coefficients for each predictor
A Mixed ANOVA design would be appropriate for which of the following situations?
A Different participants are tested in each condition
B All participants are tested in all conditions
C Participants are tested in all conditions for at least one IV, and different participants are tested in each condition for at least one IV
D None of the above
C
In a one-way independent ANOVA with 40 participants and 5 conditions of the IV, what are the degrees of freedom for the between-groups Mean Squares (MSbetween)?
4
How many IV’s and DV’s are there in a two-way ANOVA
Two IV, 1 DV
In a two-way factorial design, the SSR (residual sum of squares) consists of what?
Variance which cannot be explained by the independent variables
What is the non-parametric equivalent of a one-way repeated measures ANOVA?
Friedman Test
What is a limitation of the Chi-square test?
A It cannot be used when you have more than 2 categorical variables
B Directional hypotheses are not possible when you have more than two conditions of a variable
C A small sample size can result in an unreliable test statistic
Are directional hypotheses possible with chi-square?
Yes, but ONLY when you have a 2x2 design
What is the difference between a loglinear model and a chi-square test?
loglinear is an extension of chi-square test,
LL models can determine complex interactions in multidimensional contingency tables with more than two categorical variables whereas a chi can only analyse two variables at a time
When conducting a loglinear analysis, if our model is a good fit of the data then goodness-of-fit statistic for the final model should be what?
non-significant (p = >0.05)
Example:
An organizational psychologist is hired as a consultant by a person planning to open a coffee house for college students. The coffee house owner wants to know if her customers will drink more coffee depending on the ambience of the coffee house. To test this, the psychologist sets up three similar rooms, each with its own theme (Tropical; Old Library; or New York Café ) then arranges to have thirty students spend an afternoon in each room while being allowed to drink all the coffee they like. (The order in which they sit in the rooms is counterbalanced.) The amount each participant drinks is recorded for each of the three themes.
- Independent variable(s)
- Is there more than 1 IV?
- The levels the independent variable(s)
- Dependent variable
- Between (BS) or within-subjects (WS)?
- What type of design is being used?
- Theme
- No
- Tropical, old library, new york cafe
- Amount of coffee consumed
- Within
- 1-way repeated measures
A manager at a retail store in the mall wants to increase profit. The manager wants to see if the store’s layout (one main circular path vs. a grid system of paths) influences how much money is spent depending on whether there is a sale. The belief is that when there is a sale customers like a grid layout, while customers prefer a circular layout when there is no sale. Over two days the manager alternates the store layout, and has the same group of customers come each day. Based on random assignment, half of the customers told there is a sale (20 % will be taken off the final purchases), while the other half is told there is no sale. At the end of each day, the manager calculates the profit.
1. Independent variable(s)
2. Is there more than 1 IV?
3. The levels the independent variable(s)
4. Dependent variable
5. Between (BS) or within-subjects (WS)?
6. What type of design is being used?
- Sale/No Sale, Store’s layout
- Yes
- Sale vs No Sale, Grid vs Circular
- Profit
- BS (Sale) and WS (Layout)
- 2-way mixed measures
A researcher at a drug treatment center wanted to determine the best combination of treatments that would lead to more substance free days. This researcher believed there were two key factors in helping drug addiction: type of treatment and type of counseling. The researcher was interested in either residential or outpatient treatment programs; and either cognitive-behavioral, psychodynamic, or client-centered counseling approaches. As new clients enrolled at the center they were randomly assigned to one of six experimental groups. After 3 months of treatment, each client’s symptoms were measured.
1. Independent variable(s)
2. Is there more than 1 IV?
3. The levels the independent variable(s)
4. Dependent variable
5. Between (BS) or within-subjects (WS)?
6. What type of design is being used?
- Type of treatment, type of counseling
- Yes
- Residential or outpatient/cb, psychodynamic or client centered
- Substance free days
- BS
- 2 way independent measures ANOVA