Psychology 2801 Practice Exam Answers
1) A researcher would like to test the effectiveness of a newly developed growth hormone. The researcher knows that under normal circumstances laboratory rats reach an average weight of = 950 grams at 10 weeks o
Psychology 2801 Answers to the Practice Problems 1) A psychologist obtained the following set of data: 3, 8, 13, 23, 26, 26, 26, 27, 28, 28, 29, 30, 32, 41, 49, 56 a) Calculate the mean, median, and mode for these data. Mean = (445) / 16 = 27.8125 Me
Introduction to Psychological Measurement and Data Analysis
PSY 2801

Summer 2010
Notes
PSY 2801: Summer 2010
One Sample Tests/Condence Intervals
Je Jones
University of Minnesota
Je Jones
Hypothesis Tests for Means
Notes
The rst several statistical tests have the same form: H0 : = 1 H1 : = 1 That is for the twosided test. We want to t
Introduction to Psychological Measurement and Data Analysis
PSY 2801

Summer 2010
PSY 2801: Summer 2010
Linear Regression
Je Jones
University of Minnesota
Je Jones
Scatterplot Revisited
1
An Example Scatterplot
The linear measure of association
The typical increase in y for an increase in x
+
3
+ + + + + + + + + + + + + + + + + + + + +
Introduction to Psychological Measurement and Data Analysis
PSY 2801

Summer 2010
Sampling Distributions Central Limit Theorem
Notes
PSY 2801: Summer 2010
Sampling Distributions
Je Jones
University of Minnesota
Je Jones
Ch 8
Sampling Distributions Central Limit Theorem
Sampling Distributions
Notes
A Sampling Distribution is a distribut
Introduction to Psychological Measurement and Data Analysis
PSY 2801

Summer 2010
Notes
PSY 2801: Summer 2009
zscores/Normal Distribution
Je Jones
University of Minnesota
Je Jones
Ch 6
Data Transformations
Notes
Often, your data will make more sense in a dierent form. For instance, if you have interval data, then the 0 point doesnt ma
Introduction to Psychological Measurement and Data Analysis
PSY 2801

Summer 2010
Graphing
Notes
PSY 2801: Summer 2010
Graphing
Je Jones
University of Minnesota
Je Jones
Lecture 2
Graphing
CH 3
Why Plot?
Notes
Our eyes dont see patterns in a lot of random numbers So, to make sense of a lot of data, the best thing to do is to rst visual
Introduction to Psychological Measurement and Data Analysis
PSY 2801

Summer 2010
Central limit T
Given a population distribution with a mean and a variance 2, the sampling distribution of the mean using sample size N (or, to put it another way, the distribution of sample means) will have a mean of x = and a variance equal to 2 = 2 , w
Introduction to Psychological Measurement and Data Analysis
PSY 2801

Summer 2010
Null Hypothesis Signicance Testing
Notes
PSY 2801: Summer 2010
Hypothesis Testing
Je Jones
University of Minnesota
Je Jones
Null Hypothesis Signicance Testing
Null Hypothesis Signicance Testing
Notes
For the rest of the semester, we will attempt statistic
Introduction to Psychological Measurement and Data Analysis
PSY 2801

Summer 2010
Final Review/Outline (Last 1/3 of the Material)
Here is a list of basic terms and concepts that we have discussed since the second midterm. Since the Final is cumulative, the other two review sheets are also good places to help focus your studies. Please
Introduction to Psychological Measurement and Data Analysis
PSY 2801

Summer 2010
Descriptive Statistics Central Tendency Variability Shape
Notes
PSY 2801: Summer 2010
Descriptive Statistics
Je Jones
University of Minnesota
Je Jones
Chs 4 and 5
Descriptive Statistics Central Tendency Variability Shape
Notes
Descriptives versus Inferent
Introduction to Psychological Measurement and Data Analysis
PSY 2801

Summer 2010
Chi Square (2 )
PSY 2801: Summer 2010
Chi Square (2 ) Je Jones
University of Minnesota
Je Jones
Chi Square (2 )
Count Data
So, we can perform tests on Interval/Ratio Scale measures, and we can pretend that Ordinal Scale measures are Interval Scaled (they
Introduction to Psychological Measurement and Data Analysis
PSY 2801

Summer 2010
OneWay ANOVA
PSY 2801: Summer 2010
OneWay ANOVA Je Jones
University of Minnesota
Je Jones
OneWay ANOVA
(More Than) Two Independent Samples
There is (at least) one caveat with the ttests we have learned: we have no way of performing a test with more th
Name _ Section Number _
Psychology 2801 Testing the Null
Suppose I have strong evidence that the mean for my sample of children is greater than the general population. The onetailed critical z using an of .05 equals _. I would reject the null if m
Name _ Section Number _
Psychology 2801 Testing the Null
Suppose I have strong evidence that the mean for my sample of children is greater than the general population. The onetailed critical z using an of .05 equals _1.645_. I would reject the nul
Introduction to Psychological Measurement and Data Analysis
PSY 2801

Summer 2010
PSY 2801: Summer 2009 Lab Assignment 9
(ANOVA/Chi Square) Due Wednesday, August 18, 2009
Please show all of the work for your calculations Where appropriate, include SPSS output 9.1
Research Question: A researcher is hired by a television network to inves