1. Introduction to Statistics for the Social Sciences SBS200 - Lecture Section 001, Fall 2016 Room 150 Harvill Building 10: :50 Mondays, Wednesdays & Fridays.
Welcome

2. Lab sessions Everyone will want to be enrolled
in one of the lab sessions
No Labs
this week

3. Schedule of readings Before next exam (September 23rd)
Please read chapters in OpenStax textbook
Please read Appendix D, E & F online On syllabus this is referred to as online readings 1, 2 & 3
Please read Chapters 1, 5, 6 and 13 in Plous
Chapter 1: Selective Perception
Chapter 5: Plasticity
Chapter 6: Effects of Question Wording and Framing
Chapter 13: Anchoring and Adjustment

4. Homework Assignment 4 Integrating Methodologies and Graphing with Excel
Please print out and complete this homework worksheet
And hand it in during class on Friday
Due: Friday, September 9th
This worksheet can be found on our regular class website and printed out to be completed (not on D2L)

5. By the end of lecture today 9/7/16
Use this as your
study guide
By the end of lecture today 9/7/16
Frequency distributions and Frequency tables
Guidelines for constructing frequency distributions
1. Classes should be mutually exclusive
2. Set of classes should be exhaustive
3. All classes should have equal intervals
4. Selecting number of classes is subjective (5 -15 will often work)
5. Class width should be round (easy) numbers
6. Try to avoid open ended classes
Cumulative Frequency
Relative Frequency and percentages
Predicting frequency of larger sample based on relative frequency
Pie Charts
Relative Cumulative Frequency

6. Let’s try one
When Martiza was preparing her experiment, she knew it was important that the participants not know which condition they were in, to avoid bias from the subjects.
This is called a _____ study.
She also was careful that the experimenters who were interacting with the participants did not know which condition those participants were in.
This is called a ____ study.
a. between participant; within participant
b. within participant; between participant
c. double blind design; single blind
d. single blind; double blind design

7. Let’s try one A measurement that has high validity is one that
a. measures what it intends to measure
b. will give you similar results with each replication
c. will compare the performance of the same subjects
in each experimental condition
d. will compare the performance of different subjects

8. Let’s try one
A study explored whether conservatives or liberals had more bumper stickers on their cars. The researchers ask 100 activists to complete a conservative/liberal values test, then used those results to categorize them as liberal or conservative. Then they identified the 30 most conservative activists and the 30 most liberal activists and measured how many bumper stickers each activist had on their car. The independent variable in this study was
a. the performance of the activists
b. the number of bumper stickers found on their car
c. political status of participant (liberal versus conservative) as determined by their performance on the liberal/conservative test
d. whether or not the subjects had bumper stickers on their car c.

9. Let’s try one
A study explored whether conservatives or liberals had more bumper stickers on their cars. The researchers asked 100 activists to complete a conservative/liberal values test, then used those results to categorize them as liberal or conservative. Then they identified the 30 most conservative activists and the 30 most liberal activists and measured how many bumper stickers each activist had on their car. The dependent variable in this study was
a. the performance of the activists
b. the number of bumper stickers found on their car
c. political status of participant (liberal versus conservative) as determined by their performance on the liberal/conservative test
d. whether or not the subjects had bumper stickers on their car b.

10. Let’s try one
A study explored whether conservatives or liberals had more bumper stickers on their cars. The researchers 100 activists to complete a conservative/liberal values test, then used those results to categorize them as liberal or conservative. Then they identified the 30 most conservative activists and the 30 most liberal activists and measured how many bumper stickers each activist had on their car. This study was a
a. within participant experiment
b. between participant experiment
c. mixed participant experiment
d. non-participant experiment b.

11. Let’s try one
A study explored whether conservatives or liberals had more bumper stickers on their cars. They had 100 activists complete liberal/conservative test. Then, they split the 100 activists into 2 groups (conservatives and liberals). They then measured how many bumper stickers each activist had on their car. This study used a
a. true experimental design
b. quasi-experiment design
c. correlational design
d. mixed design b.

12. Writing Assignment – Pop Quiz
Ari conducted a watermelon seed spitting experiment. She wanted to know if people can spit farther if they get a running start. She tested 100 people. She randomly assigned them into one of two groups. One group stood still on the starting line and spit their watermelon seeds as far as they could. The second group was allowed to run up to the starting line before they spit their watermelon seeds. She measured how far each person spit their watermelon seeds.
Please answer the following questions
1. What is the independent variable?
2. The independent variable: Is it continuous or discrete?
3. The independent variable: Is it nominal, ordinal, interval or ratio?
4. What is the dependent variable?
5. The dependent variable: Is it continuous or discrete?
6. The dependent variable: Is it nominal, ordinal, interval or ratio?
7. Is this a quasi or true experiment?
8. Is this a within or between participant design
9. Is this a single blind, double blind or not at all blind experiment?
10. Be sure to put your name and CID on this page

13. Writing Assignment – Pop Quiz
Ari conducted a watermelon seed spitting experiment. She wanted to know if people can spit farther if they get a running start. She tested 100 people. She randomly assigned them into one of two groups. One group stood still on the starting line and spit their watermelon seeds as far as they could. The second group was allowed to run up to the starting line before they spit their watermelon seeds. She measured how far each person spit their watermelon seeds.
Running versus standing still
Please answer the following questions
1. What is the independent variable?
2. The independent variable: Is it continuous or discrete?
3. The independent variable: Is it nominal, ordinal, interval or ratio?
4. What is the dependent variable?
5. The dependent variable: Is it continuous or discrete?
6. The dependent variable: Is it nominal, ordinal, interval or ratio?
7. Is this a quasi or true experiment?
8. Is this a within or between participant design
9. Is this a single blind, double blind or not at all blind experiment?
10. Be sure to put your name and CID on this page
Discrete
Distance that the seed was spit
Nominal
Continuous
True Experiment
Ratio
Between
Not at all

14. You’ve gathered your data…what’s the best way to display it??

15. Describing Data Visually
Lists of numbers too hard to see patterns
Describing Data Visually
Organizing numbers helps
Graphical representation even more clear
This is a dot plot

16. Describing Data Visually
Measuring the “frequency of occurrence”
We’ve got to put these data into groups (“bins”)
Then figure “frequency of occurrence” for the bins

17. Frequency distributions
Frequency distributions an organized list of observations and their frequency of occurrence
How many kids are in your family?
What is the most common family size?

18. Another example: How many kids in your family?
Number of kids in family
1 3
1 4
2 4
2 8
2 14 14 4 2 1 4 2 2 3 1 8

19. Frequency distributions
Number of kids in family
1 3
1 4
2 4
2 8
2 14
How many kids are in your family?
What is the most common family size?
Frequency distributions
Crucial guidelines for constructing
frequency distributions:
1. Classes should be mutually exclusive: Each observation
should be represented only once (no overlap between classes)
Wrong
0 - 5
5 - 10
Correct
0 - 4
5 - 9
Correct
0 - under 5
5 - under 10
10 - under 15
2. Set of classes should be exhaustive:
Should include all possible data values
(no data points should fall outside range)
Wrong
0 - 4
8 - 11
Correct
0 - 3
4 - 7
No place for our families of 4, 5, 6 or 7

20. Frequency distributions
Number of kids in family
1 3
1 4
2 4
2 8
2 14
How many kids are in your family?
What is the most common family size?
Frequency distributions
Crucial guidelines for constructing
frequency distributions:
3. All classes should have equal intervals
(even if the frequency for that class is zero)
Wrong
0 - 1
2 - 12
Correct
0 - 4
5 - 9
Correct
0 - under 5
5 - under 10
10 - under 15

21. 4. Selecting number of classes is subjective
4. Selecting number of classes is subjective
Generally will often work
How about
6 classes? (“bins”)
How about
16 classes? (“bins”)
How about
8 classes? (“bins”)

22. Lower boundary can be multiple of interval size
5. Class width should be round (easy) numbers
Remember: This is all about helping readers understand quickly and clearly.
Lower boundary can be multiple of interval size
Clear & Easy
8 - 11
Round numbers:
5, 10, 15, 20 etc or
3, 6, 9, 12 etc
6. Try to avoid open ended classes
For example
10 and above
Greater than 100
Less than 50

23. Let’s do one Step 1: List scores Step 2: List scores in order
Scores on an exam
Let’s do one 53 58 60 61 64 69 70 72 73 75 76 78 80 82 84 87 88 89 91 93 94 95 99
Step 1: List scores
Step 2: List scores in order
Step 3: Decide whether grouped or ungrouped
If less than 10 groups, “ungrouped” is fine
If more than 10 groups, “grouped” might be better
How to figure how many values
Largest number - smallest number + 1
= 47
Step 4: Generate number and size of intervals (or size of bins)
If we have 6 bins – we’d have intervals of 8
Sample
size (n)
10 – 16
17 – 32
33 – 64
65 – 128
256 – 511
512 – 1,024
Number of classes 5 6 7 8 9 10 11
Let’s just try it and see which we prefer…
Whaddya think?
Would intervals of 5 be easier to read?

24. Let’s just try it and see which we prefer…
Scores on an exam
Scores on an exam
Score Frequency
80 – 84 5
Scores on an exam
Score Frequency 53 58 60 61 64 69 70 72 73 75 76 78 80 82 84 87 88 89 91 93 94 95 99
Let’s just try it and see which we prefer…
6 bins
Interval of 8
10 bins
Interval of 5
Scores on an exam
Score Frequency
80 – 84 5
Remember: This is all about helping readers understand quickly and clearly.

25. Let’s make a frequency histogram using 10 bins and bin width of 5!!
Scores on an exam
Scores on an exam
Score Frequency
80 – 84 5
Let’s make a
frequency histogram
using 10 bins and
bin width of 5!!

26. Step 6: Complete the Frequency Table
Scores on an exam
Step 6: Complete the Frequency Table
Scores on an exam
Score Frequency
80 – 84 5
Relative Cumulative
Frequency
1.0000
.9285
.8214
.6428
.4642
.3213
.2142
.1785
.0714
.0357
Cumulative
Frequency 28 26 23 18 13 9 6 5 2 1
Relative
Frequency
.0715
.1071
.1786
.1429
.0357
Just adding up the relative frequency data from the smallest to largest numbers
Please note:
Also just dividing cumulative frequency
by total number
1/28 = .0357
2/28 = .0714
5/28 = .1786
Just adding up the frequency data from the smallest to largest numbers
6 bins
Interval of 8
Just dividing each frequency by total number to get a ratio (like a percent)
Please note:
1 /28 = .0357
3/ 28 = .1071
4/28 = .1429

27. “Who is your favorite candidate?”
Simple Frequency Table – Qualitative Data
Who is your favorite candidate
Candidate Frequency
Hillary Clinton 45
Bernie Sanders 23
Joe Biden 17
Jim Webb 1
Other/Undecided 14
Number expected to vote
9,900,000
5,060,000
3,740,000
220,000
3,080,000
We asked 100 Democrats
“Who is your favorite candidate?”
Relative
Frequency
.4500
.2300
.1700
.0100
.1400
Percent
45%
23%
17% 1%
14%
If 22 million Democrats voted today how many would vote for each candidate?
Just divide each frequency by total number
Just multiply each relative frequency by 22 million
Just multiply each relative frequency by 100
Please note:
45 /100 = .4500
23 /100 = .2300
17 /100 = .1700
1 /100 = .0100
Please note:
.4500 x 22m = 9,900k
.2300 x 22m = 35,060k
.1700 x 22m = 23,740k
.0100 x 22m= 220k
Please note:
.4500 x 100 = 45%
.2300 x 100 = 23%
.1700 x 100 = 17%
.0100 x 100 = 1%
Data based on Gallup poll on 8/24/11

31. Thank you!
See you next time!!