Before we look at the p-value, we must look at the alpha. What is the standard alpha level?
.05
What is a one-sample T-test doing?
Comparing a sample mean to a known population mean
Is Chi-Square Goodness of Fit bivariate or univariate?
Univariate
Is the Chi-Square Test of Independence bivariate or univariate?
Bivariate
What is the purpose of a Correlation analysis testing?
- measures the association (strength) of the relationship between 2 variables
- measures the linear relationship between 2 variables ONLY (IV and DV)
What is the purpose of the p-value?
- to tell us the significance level
- to make a decision
What is an independent sample t-test doing?
Comparing means from two independent groups
Looking for a relationship between two variables
What is the purpose of the Chi-Square Goodness of Fit test?
- used to test and compare the frequencies (categories/levels) within one variable
What are keywords to remind us of when to use/look for a Chi-Square Test of Independence?
- Nominal/Qualitative
- 2 variables with multiple levels
- Relationship
What is the number that indicates a strong positive linear relationship? a strong negative linear relationship?
+1 and -1
If P is ≤ alpha, _______, ________.
If P is ≤ alpha, significant, reject null hypothesis.
What is a dependent sample t-test doing?
Comparing mean scores within the same group
Within the Chi-Square Goodness of Fit test, what kind of variable is used? How many levels?
Do both variables have to be qualitative to be considered a Chi-Square Test of Independence?
Yes.
What kind of graph does a Correlation use?
Scatterplot
If P is ≥ alpha, _______, _________.
If P is ≥ alpha, not significant, fail to reject null hypothesis.
What are the three types of dependent samples?
Paired, related, matched
What are some keywords to remind us of when to use/look for Chi-Square Goodness of Fit?
- Nominal/Qualitative
- 1 variable multiple levels (frequencies/categories)
What is the purpose of the Chi-Square Test of Independence?
- Used to test the relationship between 2 qualitative (nominal/categorical) variables with multiple levels
What are keywords to remind us of when to use/look for a Correlation testing?
- relationship
- bivariate
- scale
- correlate, related
If P is .001 and alpha is .05, what do we do?
P (.001) ≤ alpha (.05)
Reject the null hypothesis.
Which t-test is this?
Researchers want to test a new anti-hunger weight loss pill. They have 10 people rate their hunger both before and after taking the pill.
Dependent (paired) sample t-test
Q: Are there more Pugs at the dog park than Chihuahuas, or Schnauzers?
What is the variable? How many levels?
Variable: Dog breeds
Levels: 3
Q: Do psychology majors and biology majors do the same activities of going to the park, going for a swim, and going out to eat?
What are the variables? How many levels to the variables?
IV: Majors
levels: 2- psychology and biology
DV: types of activities
levels: 3- going to the park, going for a swim, and going out to eat
Describe a positive correlation and a negative correlation.
Positive correlation: as one variable goes up the other also goes up. as one variable goes down the other also goes down (same behavior)
Negative correlation: as one variable goes up the other goes down (opposites)