Introduction to Statistics (PS 240-02)

Spring 2008-2009

 

Professor:  L.W. McCallum                                                              Office: Evald 15

 

Phone: 794-7373(work)                                                                     Hours: by appointment

                 563-355-3474                                                    

                                                                                                                e-mail:larrymccallum@Augustana.edu

                                                                                                                website: www.augustana.edu/users/psmccallum

 

Text:    Gravetter, F. J.  & Wallnau, L. B. (2008).  Essentials of Statistics for the Behavioral

 Sciences 6th ed. Belmont, CA: Wadsworth/Thomson.  

 

(FYI:  There is a free website for the text. Go to www.thomsonedu.com/psychology/gravetter, find “Student” and click on “companion site”)

 

***You will also need a calculator that can determine square roots – anything more sophisticated than that is not necessary.  Please bring your calculator to class and lab everyday.

 

P.A.:  Katie McCarthy is available for individual tutoring.  Her office hours are MWF: D Period and TTh: G Period.  Remember that she is a full-time student and is only at “work” for the psychology department during her office hours. Don’t stalk her across campus or in the library, don’t call her at 2am, and don’t expect her to have all the answers or to know what is going to be on the test.  Please do visit her for office hours and attend study sessions.   If her schedule does not fit yours or you need additional tutoring, let me know and I’ll make arrangements for that to happen.

 

 

This course has been developed in accordance with the skills x levels approach adopted by the Psychology Department.  This means that in addition to learning content (e.g., the difference between nominal and ordinal scales, which correlation coefficient is appropriate with various measures) you are expected to develop skills identified as appropriate for someone taking an introductory course in statistics.  Specifically, the skills you will develop in this class are;

a.    critically evaluate statistics from popular (e.g., Newsweek) and professional (e.g., Journal of Experimental Psychology) sources

b.    select and conduct an appropriate statistical test when presented with a data set or research question

c.    interpret the results of major statistical analyses

d.    understand the appropriate use of statistics and evaluate their use in terms of reliability and validity

e.    utilize the major functions of SPSS

f.     present statistics in APA style.

 

Academic integrity.  All course requirements will be completed by the student him/herself.  In other words, you will do your own homework and take the exams without the use of crib sheets or the voluntary/involuntary help of others.  I’m sure you know the difference between working together on homework assignments and copying a colleagues’ work – the first is acceptable, the second is cheating.  If you work with another student on homework, please paperclip the sheets together when you turn them in so that we can grade them more easily.  In cases of plagiarism and/or cheating, I will follow the policies outlined in the Augustana Student Handbook. 

 

 

Course Work

 

Homework will be assigned for each chapter.  It is the minimum you should do to learn statistics – if you struggle with the problems, do more of them until you are more confident in your abilities.  Remember that Katie is not available to help you or if you are confused or you can see me. Please email or call to make an appointment.  Please make your calculations as legible in order to facilitate the grading of it.  Circle your final answer when possible.  It will be returned to you much more quickly if we can read it.  If we can’t follow your procedures and/or find your answers, it will be recorded as incomplete.

 

Homework will be assigned for each of the 14 chapters we cover and will be due on specified days (see schedule).  Each set of homework will be graded on a 5 point scale and 10 of the chapters will count towards your final grade.  In other words, you may “skip” four chapters of homework without being penalized, but after that you will begin to lose points towards your final grade in the class.  Homework that is turned in late, is illegible, or incomplete will not be graded.

 

 

Lab Projects.  Each Tuesday (beginning week 2) at 2:30 we will have a stats lab in Olin 109.  Please note that there is no class on that day. .The activities that we do in lab are designed to give you a first-person perspective on statistics.  The topics in lab are paired with the material that we discuss in class. There are 9 lab dates, but I will count only your best 8 at 10 points each.

 

Exams.  There will be 5 exams throughout the course.  You will find the content of the exams to reflect the Unit Goals as indicated on the “Course Schedule.” 

 

 

COURSE GRADE:  Your final grade will be determined by the points earned on these components:

                Exams 1, 2, 3, & 4, each worth 100 points =  400

                Exam #5 and the lab practical                         100

                Homework (5 pts. per chapter)                            50

                8 weeks of lab activities =                                     80

                                                             TOTAL POINTS  = 630

 

 

A=90%=567

B=80%=504

C=70%=441

D=60%=378

 

 

Absences & Missed tests

 

Please attend all classes. Statistics is necessarily cumulative in that you really must master one concept before moving on to the next.  If you must miss a class, please let me know beforehand or make arrangements to get notes from a classmate.  If you must miss a test or if you will not be present to turn in homework on the due date, then you must notify me in advance so that we can make the appropriate arrangements. If you fail to inform me prior to the scheduled date, then you will not be allowed to make it up. You also should be aware that make up tests will include a separate set of problems from the original test and is likely to be slightly more difficult. Remember that there is a substantial penalty for habitually ignoring one's homework.

 

 

A few final words before the schedule is presented

 

1) If you are struggling with something in the homework, please let me know as soon as possible!  Do not

    wait until the last week of the term to see me about problems. I can help students with their class-related

    problems in most situations, but the sooner we solve the problem, the better. See me early!

 

2) Many people approach Statistics with fear because they don’t see themselves as a “math” person . Do

    not be afraid of numbers in statistics. We are using simple math that is taught in jr. high. I have some tips

    for any math-phobics out there and will be glad to work with you.

 

3) It’s really easy to fall behind in the early chapters, especially for those who are already comfortable with

    basic descriptive statistics. My advice is to keep up every step of the way.   Everything in units 3, 4 & 5

    depend on and use the calculations from units 1 & 2.

 

4) There is no extra credit in this course. Students earn grades by keeping up with the homework

    and then applying what they learned in the assignments to the tests.

 

Special Syllabus Supplement:  How to Type Statistics

 

In statistics, we use lots of notation to abbreviate and indicate mathematical operations. Much of this notation uses greek symbols   Here is a quick index of common notation and how to type it in MSWord.

 

This  symbol

is pronounced….

it represents….

and to type it, you will

m

"mew"

the mean (average) of a population

type a lower case "m" in symbol font

S

"sigma"

adding up a set of numbers

type an upper case "S" in symbol font

 

s

"sigma"

the standard deviation of a population

type a lower case "s" in symbol font

X2

(superscript)

"x-squared"

a variable times itself, in other words, X times X

type a regular X2, then select the 2, use the format menu, Font, and check "superscript"

mseniors

(subscript)

"the mean of seniors"

The mean of a group, in this case "seniors" but could be anyone or anything you want

type the notation that will remind you what the mean represents (e.g. seniors), select the word (not m), go to Format, Font, and check "subscript"

"the square root of"

calculating the square root of a number, e.g.    4 = 2

use the Insert menu, select Symbol, and find the in that menu

"does not equal"

exactly what it sounds like

use the Insert menu, select Symbol, and find the ≠ in that menu

ŷ

"y-hat"

predicted value of y at a given value of x; the least squares regression line

use the Insert menu, select Symbol, and find the ŷ in that menu

H0

or H1

"null hypothesis" or "alternative hypothesis"

the mutually exclusive outcomes of a statistical test

type H0 (zero)  or H1, then using the subscript function to drop the numeral, like so H0

 

Course Schedule

Unit 1: Basic Vocabulary & Descriptive Statistics

 

 

Date

Chapter

Topic

Tests/Assignments

M 3/9

1

Meet People

Why study statistics?

 

 

W

3/11

1

Scales of measurement, Types of Variables

 

Ch 1: 2, 10, 14,16, 20, 24

 

 

F

3/13

2

Frequency Distributions & Graphs

 

Ch 2: 2,8,10,12,16,20

HW 1 due today

 

M

3/16

3

Central tendency – Come to class knowing how to compute mean, median, mode!

Ch 3: 4-14(even) 22, 24

HW 2 due today

 

W

3/18

4.1, 4.2 &

4.3-4.5

Variability – Sums of Squares,

Standard Deviation and Variance

Ch 4: 2,4,14,20,22, 26

HW 3 due today

 

F

3/20

 

TEST 1

Test on Ch. 1-4

HW 4 due today

 

Unit 1 Goals:  By Test 1, students should be able to…

(A) provide definitions and examples for the four scales of measurement and the two 'types' of variables.

(B) distinguish experimental and correlational methods and identify the variables in each.

(C) create full frequency distribution tables (with groups when appropriate).

(D) create graphs appropriate to the type of data &identify elements of a graphing which may be misleading. (E) calculate and interpret basic descriptive statistics (mean, median, mode, ranges, variance)

(F) select the best descriptive stats and graphs for a given type of data (nominal, interval, etc.) or problem

(G) predict how a descriptive statistic will change with certain changes in data (e.g., if the highest point in the data set doubled, how would that affect the mean? the median?)

Don’t forget the “rules” and conventions for creating groups, tables, and graphs!


 

Unit 2: Standardization & Probability in Normal Distributions

 

 

Date

Chapter

Topic

Tests/Assignments

M

3/23

5

Introduction to Normality and Z scores

Ch 5: 4,6,12,14,18,20,24,28

 

 

W

3/25

6

Probability

HW 5 due today

Ch 6: 2,6,8,10,12,18,22

 

F

3/37

6

Review Z scores, HW

H HW 6 due today

 

M

3/30

7

Sampling distribution and sampling error

Ch 7: 2,4,8,10,14,18,20,24

 

W

4/1

5-7

Confidence Intervals;

Review & Pretest chapters 5-7

HW 7 due today

 

F

4/3

 

TEST 2

Test on Ch. 5,6,7

 

 

Unit 2: By Test 2, students should be able to…

 (A) standardize data by converting from raw scores to z scores and back again.

 (B) use the z table to identify percentages identified with certain z scores & ranges

 (C) differentiate between distributions of observations and sampling distributions.  

 (D) Build confidence intervals for m

 (E) Describe how different elements of a sample affect sampling distributions (mostly n and S)

 

 

 

Unit 3: Inferential Statistics

 

 

 

Date

Chapter

Topic

Tests /Assignments

M

4/6

8

Hypothesis testing

Ch 8: 1-5, 8, 10, 16, 20

 

W

4/8

9

t- tests

HW 8 due today

Ch9: 1, 2, 8, 16,18

 

T

4/14

10

 

Independent  t -tests

HW 9 due today

Ch 10: 2,4,12,14, 18, 24

 

W

4/15

11

Dependent t tests

 

Ch 11: 1, 2, 3, 4, 10, 20,24

 

F

4/17

 

Review chapters 8-11

HW 10 & 11 due today

 

M

4/20

 

complete in-class projects/pretest

 

 

W

4/22

 

Test 3

Test on Ch. 8, 9, 10, 11

 

By Test 3, students should be able to….

A) differentiate between distributions of observations and sampling distributions.  

B) identify and conduct the most appropriate hypothesis tests (e.g. 1 sample ind. vs. dependent -t)

C) define both types of error involved in these tests and how to control them.

D) explain effect size and distinguish between statistical and practical significance.

E)  identify the four elements that most influence the outcome of a t-test

 

 


 


Unit 4: ANOVA

 

 

Date

Chapter

Topic

Tests/Assignments

F

4/24

13

One way ANOVA 

 

Ch 13: 1, 3, 4, 5, 8, 10*, 18*, 24*

* Include an HSD test

 

M

4/27

13

One way ANOVA 

Including Post hocs

 

W

4/29

14.1 & 14.3

Two Factor ANOVA

    We will not calculate this from raw data

HW 13 due today

Ch 14: 18, 20, 22, 24,26

 

F

5/1

14.2

Repeated measures ANOVA

 

 

M

5/64

 

Review & Pretest for ANOVAs

HW 14 due today

 

W

5/6

 

TEST 4

Test on Ch. 13, 14.1, 14.3

 

 

By Test 4, students should be able to…  

(A) draw comparisons between Unit 3 hypothesis tests and Unit 4 tests in terms of comparing the t test statistic to the F test statistic, understanding the effects of sample size, and describing the effects of error/variability within independent samples.

 (B) calculate Independent 1-way ANOVA (including  Post-hoc tests) from raw data and test Factorial ANOVAs as well. 

 (C) identify the correct ANOVA (1-way between groups, 1-way within groups, and all varieties of factorial designs) given a specific type of data or practical problem.

 (D) describe the rationale behind the use of post hoc tests.

 (E) explain exactly how and why variance is analyzed (broken down).

 

 

 

 

Unit 5: Correlation & Regression Analyses

Date

Chapter

Topic

Tests/Assignments

F

5/8

15.1-15.4

Pearson Correlation

Ch 15: 3, 6, 8, 10, 18, 20

M

5/11

15.6

Regression equations

 

W

5/13

15.7

Additional considerations

 

 

F

5/15

16

Chi-square tests

Ch. 16: 2, 12, 14, 18

HW 15  & 16 due today

 

 

 

 

M 9/18                          TEST 5                                                                         Test on Ch. 15

NOON

 

By the final exam date, students should be able to…   

(A) explain how regression and correlation relate to the mean and variability (i.e., the mean squared error) of a single dependent variable.

(B) calculate and test Pearson correlation coefficients and then interpret results (paying close attention to causal interpretations).

(C) use regression to make predictions for X or Y variables & describing the accuracy of those predictions in terms of variance.

(D) Identify data requirements for correlation & regression and potential problems with sampling and interpretation (ordinal data & Spearman's R; nonlinearity, etc.)

           

 

 

Lab Schedule