Ni Chen
PSYCH STATISTICS
MW9A
TEXTBOOK PROBLEMS
2. You fill out a survey question that asks you to give the likelihood that you will vote in an
upcoming election. The question uses a 5-point response scale from 1 = not at all likely to 5 =
very likely and
Assignment #7: t Statistic (10 points)
Due 3/25 by 3pm. Late assignments will not be accepted. Submit a HARD COPY.
Show all of your work. Round to 3 decimal places.
1.
2. (0.5
pts) Why is the t
distribution
flatter and more spread out than that the
normal
Statistical
POWER!
State of Reality
Experimental Decision
H0 is True
Correct Decision
Retain H0
Reject H0
H0 is false
Type II Error
The drug doesnt work and my
experiment concluded that it
doesnt work.
The drug works but my
experiment concluded that it
do
Psychological Statisti
cs Lab week7
Junqing Chen
Email : [email protected]
Office hour: 4:00 5:00 P.M., Tuesday
4405B James Hall
Goal of today
HW5
HW5
Due Oct. 22nd. Hand in the hard copy of ans
wer sheet in the lecture.
Q3 example
After removing
One-Way ANOVA: POST-HOC tests
Unplanned comparisons
If and only if our ANOVA is significant, we conduct a post-hoc
test. In this class, we will use Tukeys post-hoc test.
Example Data:
Splenda
Equal
Sweet & Low
3
6
0
4
3
1
2
2
3
5
7
1
4
4
2
Introduction to
Introduction to Analysis of Variance: The LOGIC of ANOVA
Suppose an employer wants to evaluate how long it takes his employees to
perform a typing task. He knows that his company has three levels of
training: Beginner, Intermediate, and Advanced Typing. H
Psychological Statisti
cs Lab week9
Junqing Chen
Email : [email protected]
Office hour: 4:00 5:00 P.M., Tuesday
4405B James Hall
Goal of today
Z-test calculation on HW7.
HW7
Due Nov. 5th. Hand in the hard copy of answ
er sheet in the lecture.
Th
Psychological Statisti
cs Lab week10
Junqing Chen
Email : [email protected]
Office hour: 4:00 5:00 P.M., Tuesday
4405B James Hall
Goal of today
SPSS question on HW8.
HW8
Due Nov. 12th. Hand in the hard copy of ans
wer sheet in the lecture.
The h
Introduction to Analysis of Variance: The LOGIC of ANOVA
Suppose an employer wants to evaluate how long it takes his employees to
perform a typing task. He knows that his company has three levels of
training: Beginner, Intermediate, and Advanced Typing. H
Psychological Statisti
cs Lab week8
Junqing Chen
Email : [email protected]
Office hour: 4:00 5:00 P.M., Tuesday
4405B James Hall
Goal of today
HW6
HW6
Due Oct. 29nd. Hand in the hard copy of ans
wer sheet in the lecture.
Q8 example
8) Multiple ch
Measures of
Central
Tendency&
Variability
Di Fara
Ginos
Di Fara
1
2
4
3
4
4
3
4
1
3
3
2
5
3
2
44/15
= 2.93
Ginos
2
3
2
3
2
2
4
4
4
3
2
4
3
2
4
44/15
= 2.93
What differences can we see in the
distributions of these ratings?
Measures of Central Tendency a
Case Discussions & Review
1
Heartsaver First Aid
First Aid Basics
Things to know
What is first aid?
What do you do is someone refuses
help?
Steps of Primary Survey?
What to do after an emergency is over?
2
Heartsaver First Aid
Medical Emergencies
Case 1
Normal Distribution
Objectives
Introduce the Normal Distribution
Properties of the Standard Normal
Distribution
Introduce the Central Limit Theorem
Use Normal Distribution in an inferential
fashion
Theoretical Distribution
Empirical distributions
based on
Non-Parametric Statistics Part I:
Chi-Square
Number of Trees
Two Forests
400
Mirkwood
Old Forest
300
200
100
0
Pine
Maple
Type of Tree
Oak
x2 Operates on FREQUENCY Data
Suppose we have a plot of land on which we hope to harvest wood.
Maple is more valuabl
CONFIDENCE INTERVAL OF THE
MEAN , INDEPENDENT-, AND
PAIRED-SAMPLES T-TESTS
CONFIDENCE INTERVAL OF THE MEAN
We often use limited observations (samples) to talk about or
estimate the population values from which they come.
For example: My driver friend want
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yes
Which statistical test
should I use?
Are you counting up a
number of events which
have on
Statistical Reporting Format
Statistic Letter (df) = obtained value, p decision
Examples:
A paired-samples t-test with 10 participants:
t(9) = 3.54, p<.05
A one-way between-subjects ANOVA:
F(2, 15) = 68.20, p<.05
If your results are NONSIGNIFICANT, you ty
SPSS Calculations:
How to enter your data for each statistical test type.
Single Variable/
One-Sample T-test
Correlation / Regression
Independent-Samples
T-test
Paired-Samples
T-test
One-Way ANOVA
Repeated Measures
ANOVA
Two-Way ANOVA
Probability and Sampling: Part I
What are the odds?
From Reason
From a deck of cards:
What are the odds of getting the king of spades?
1/52 or 0.0192
What are the odds of getting a king?
4/52 or 0.0769
What are the odds of getting a diamond suit?
13/52 or
THE NORMAL
DISTRIBUTION AND ZSCORES
Areas Under the Curve
Lets Practice!
x: cfw_ 3, 8, 1
Find :
SS = x2
x
3
8
1
x x
4
-1
1
4
4
16
4
-3
9
xSS
x26
x
=(26/3)
= 2.94
OR
(x)2
_
N
x
3
8
1
x
9
64
1
x = 12
x = 74
74 - (144/3) = 26
Then (26/3) = 2.94
The Philosop
Pay
Correlation: A statistic to describe the
relationship between variables
Pay
Hours Worked
Pay
Hours Worked
Hours Worked
Univariate vs. Bivariate Statistics
Univariate analyses/ graphical representations:
Frequency histograms
Measures of central tendenc
Retain or Reject H0?
Outcome
Retain or Reject H0?
Outcome
Retain or Reject H0?
Outcome
Retain or Reject H0?
Outcome
Retain or Reject H0?
Outcome
Retain or Reject H0?
Outcome
Retain or Reject H0?
Outcome
The Binomial Distribution is a sampling distribution
PSYCH 3400
Statistical Methods
CUNY Brooklyn College, Department of Psychology
Alla Chavarga
[email protected]
M2AL/M2BL: MW 2:30-345pm
M6AL/M6BL: MW 6:30-7:45pm
Room: 4607J
Office hours:
MW 4pm-6pm 2420 Boylan
Approach of the Course
In this class
Binomial Distribution & Hypothesis Testing:
The Sign Test
Trees Grown
25
Decision
Frequency
20
15
No Fertilizer
Fertilizer
10
5
0
49
51
53
Growth (cm)
55
57
The formal steps of hypothesis testing:
Step 1: State your hypotheses.
Step 2: Find the critical v
One-Sample t-test
What do these problems we have been working on have in
common?
In a population of American graduate students, individuals
earn on average $7.25/hour on alcohol, with a standard
deviation of $5. I jokingly ask whether or not graduate
stud
Problem Set I: Review
Intro, Measures of Central Tendency & Variability,
Z-scores and the Normal Distribution, Correlation,
and Regression
QUESTION 1: Short answer: What is a statistic? Give a definition and an example.
Explain how the example illustrates