Assorted things to know:
1. What does it mean if your test statistic is BIGGER than the critical value?
2.How is the critical value related to the p-value?
3.How are they related to Type I error?
Standardization and z-scores Calculate z-scores:
1. Turn z-
Statistic
Mean
Weighted Mean
Semi-Interquartile Range
General Formula
M=
n
Weighted M =
SIQR=
SS= ( M )2
Q 3Q1
2
df =n1
2=
Standard Deviation
(unbiased)
Zscore
SS
N
= 2
Z=
Z=
np
np(1 p)
Standard Error of the Mean
(SE)
M=
Z-test
Cohens d
Power
SS= (
The paired-samples t-test
PSCH 343
2-25-14
Coming up.
Quiz this Thursday
Test a week from Thursday
A brief review
Z-Test
What does the z-test compare?
What do we need to know in order to conduct a
z-test?
One-sample t-test
What does the one-sample t-tes
Central Tendency
The Mean and the Median
1-28-14
Lets Review
Which type of visual display should be used to
display
A comparison between the temperature outside
and the number of fans that attend baseball games
The average number of houses sold per yea
Visual Displays of Data
PSCH 343
1-23-14
http:/xkcd.com/688/
What is an independent variable?
What is a dependent variable?
What does it mean if a distribution is normal?
Bimodal?
Positively skewed?
What distribution is this?
What distribution
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t
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SM
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The z-test
PSCH 343
2-13-14
A brief review
Central Limit Theorem
Population
= 70
= 35
Sample sizes : 90
1. What is the mean of the distribution of means?
2. What is the standard error of the distribution of
means?
Calculating percentiles, part II
The
Standardization and z-scores
PSCH 343
2-11-14
Normal Curve
Bell-shaped curve
Unimodal
Symmetric
Mathematically defined
Discovered by examining measurement errors in
astronomy
Errors occur in a symmetric pattern, equally on
both sides of the mean
Bi
Statistics and Research Design
PSCH 343
1-16-14
Announcements
10 AM discussion section moved to room 307 in
Stevenson Hall
Andrew Jarosz office hours changed from 1-2 on
Wednesday t0 11-12 on Wednesday
courses (e.g., PSCH 242)
Why should we go
Frequency Distributions
PSCH 343
1-21-14
A quick review.
Name the four types of variables
What is the difference between a measures
reliability and a measures validity?
How is a between-subjects design different
from a within-subjects design?
Getting t
Effect Size and Power
PSCH 343
2-18-14
A brief review
Name:
Height (in.)
Ralph
76
Little Joe
73
Frank
78
Andy
69
Big Joe
72
Hans
74
George
63
Tim
65
Ryan
67
Spencer
75
= 69.3 inches, = 2.8
1) What are your hypotheses
(H0 and H1)?
2) Would you use a one-
Interactions and ANOVA
PSCH 343
3-18-14
Which test?
An experimenter wants to know if calorie
consumption differs depending on which meal a
person is eating. He has 5 people log what they
ate for breakfast, lunch, and dinner, (3
measurements for each pers
The t-test
PSCH 343
2-20-14
A brief review.
One-tailed test:
Is it in the top 5% of the
distribution?
Could also ask if in the
bottom 5%
Only used if we have a
SPECIFIC prediction
Two-tailed test:
Is it in the most extreme
5% of the distribution?
We split
ANalysis Of VAriance
PSCH 343
3-11-14
A brief presentation
t-test Decision Tree
Compare a sample to a population (M to m)
Know s: single sample z-test
Dont know s: One-sample t-test
Compare two samples (M1 to M2)
Different groups: independent-samples
Sampling and Probability
1-30-14
A brief review
When to use:
Mean
Interval/Ratio data
If you have a normal (i.e., non-skewed) distribution.
Median
Interval/Ratio/Ordinal data
If you have a skewed distribution.
If outliers are present
Mode
Nomina
Within-Groups ANOVA
PSCH 343
3-13-14
A brief review.
What is family-wise error?
A between-subjects ANOVA is calculated by
dividing the _ by the _.
Name two types of follow up tests to a significant
ANOVA
Why do we use them?
What is the difference bet