Name:_
Section: _
Homework #2
Due:
10 points
1. (2 points) Make a scatter plot with the following data from the NBA. Use attendance
as the IV. Provide an estimate of the line of best fit.
NBAticketpricesandattendancebyteam
Team
Attendance
Price($)
Team
At
Rachel Terveer
January 26, 2014
Psych Stats 31
HW1 Due Jan. 30
Lab
1. Summarize the procedure and the results of the study.
Procedure: Newspaper advertisements were distributed in central Iowa to recruit 336
adults, ranging from 18-54 years old for this s
Rachel Terveer
January 22, 2014
Psych Stats 31
Lecture 2 Notes: Intro to Statistics
o Descriptive:
Organize
Summarize
Communicate
Means, modes, standard deviation help provide information about
the data collected
o Inferential
Use sample data to make
Bar graphs
Visual depictions of
data when the
independent variable
is nominal and the
dependent variable is
scale
Each bar represents
the mean value of the
DV for each category
90
80
70
60
50
40
30
20
10
0
1st
Qtr
2nd
Qtr
3rd
Qtr
4th
Qtr
Example #3
How
Tables
Collated data collected during research
Presents descriptive and inferential statistics
Easy to read information presenting overall
findings
Stand independently of text
Although text should always accompany a table
Steps to making tables
Summ
Number
Statistic
Use
Sample
Parameter Population
Mean
Variance
SD
M
SD2 s2 or
MS
SD or s
2
Variance
Population
( X )2
2
=
N
Sample
( X M )2
2
s=
N 1
Calculating Variability
Subtract the Mean from every score
Square every deviation from the mean
Sum al
Is this value significant?
Correlation as an Inferential Stat
Pearson r, with df = n - 2 = 4
Where n is the number of data points in scatterplot
(or pairs of x and y)
Is your correlation value rare enough that it
exceeds (in either direction) some crit
x
Z=
Z-Scores
Normal Distribution
Characteristics of the Normal Probability Distribution:
The distribution is symmetric, and is often illustrated
as a bell-shaped curve.
Two parameters, (mean) and (standard
deviation), determine the location and shape
Descriptive vs. Inferential
Organize
Summarize
Communicate
Use sample
data to make inferences
about the population
Transforming observations into
variables
Variable
Physical, attitudinal, and behavioral
characteristics that can take on different values