Posted: April 25th, 2015

Behavioral Stats Midterm

Behavioral Stats Midterm

General Directions:  Complete the following questions given below.  Write the answers below each question and return this exam to Dr. Lentz.  One of the goals of this course is to learn how to do analysis and then write about it in a way the ordinary city councilman would understand.  For the written portion, write well developed paragraphs.  If you only give a three sentence or less answer you will receive a very poor grade.  The answers to these questions require the calculations to determine the answers, which you will give in part A, and then a paragraph to explain the findings to an uninformed city council member in part B.  Do not write the answer for me (I already know it) but write it so that most city council members will understand.  Remember, there are 92 points for this examination.

Part 1 :Computation

A researcher is interested in studying the relationship between commute time (defined as the number of minutes it takes a person to get to work in the morning) and job satisfaction (defined on a scale from 1 – very dissatisfied to 5 – very satisfied).  The researcher believes that a person with a longer commute time will have lower job satisfaction.  This researcher surveys 20 Valley commuters and finds the following data.

1.    Formulate a hypothesis for the researcher based on the relationship between commute and job satisfaction.  Complete the cross-tab below using the data from above.  The variable job satisfaction has been grouped as:  Satisfied (4-5 on scale); Neutral (3 on scale); and Dissatisfied (1-2 on scale).  For example: a person responding with a commute time of 22 minutes and a job satisfaction of 3 will be tabulated in the 21-40 minutes/Neutral cell in the table.   Once you have tabulated the frequencies for the table, CHANGE ALL FREQUENCIES TO PERCENTAGES.  To do this, you have to calculate Column percentage.  (20 points)

Job Satisfaction    Length of Commute (in minutes)    TOTAL
0-20 minutes    21-40 minutes    41 minutes or more
Satisfied
Neutral
Dissatisfied
TOTAL

2.    In a paragraph, answer the following.  Does the data shown in the cross-tab support the researcher’s hypothesis?  How can you tell?  Identify the IV and DV.  What happens to job satisfaction as commute increases?  Decreases or Increases?  Be specific in your answer.  I want you to mention ACTUAL PERCENTAGES as they appear in the cross-tab.   7 points

Part 2

3.    The Springfield Daily Gazette has reported that the average salary for City of Springfield employees is $81,500.  The Gazette is claiming that city employees are paid much too high, and many of the citizens (who pay the taxes to support the city) are upset.  The city council has called a special meeting to argue whether employee salaries should be cut by 10-15%.  You have collected data on employee incomes for the city (see Table 1).  In a paragraph (at least 5-6 sentences), what do the measures of central tendency and standard deviation tell about the income of city employees?  Using this information, respond to city council members.  Should employee salaries be reduced?  Why or why not?  20 points

Table 1:  City of Springfield Employee Income

Mean       $81,500
Median       $35,000
Mode       $35,000
Standard Deviation       $147,367

Part 3:   Measures of Central Tendency

The table below provides dropout rates for Arizona students (K-12) in each of the counties and also for students in state juvenile corrections facilities.  (5 points each).

Overall School Dropout Rate for Arizona Counties 2003-2004

Apache    9.8%
Cochise    6.1%
Cococino    8.3%
Gila    9.1%
Graham    7.7%
Greenlee    3.1%
Maricopa    7.7%
Mohave    10.8%
Navajo    9.0%
Pima    8.5%
Pinal    9.9%
Santa Cruz    8.1%
Yavapai    9.4%
Yuma    7.7%
La Paz    8.5%
AZ Dept. of Youth Treatment and Rehabilitation    27.3%

4.    Calculate the mean, median, mode, and standard deviation.

5.    Write a detailed descriptive analysis summarizing the data (at least 6-7 sentences) based on the measures of central tendency and standard deviation.  What is the “typical” dropout rate for Arizona?  Why?

6.    If the dropout rate for the Arizona Department of Youth Treatment and Rehabilitation was not included in the data, what would happen to the mean, median, mode, and standard deviation?  Why?

Part 4:  Interpretation

Answer each of the following questions

7.    Professional athletes are threatening to strike because they claim that they are underpaid.         The team owners have released a statement that says, “the average salary for players was     $1.2 million last year.”  The players counter with their own statement that says, in part,     “the average players earned only $750,000 last year.”  Is either side necessarily lying?      Hearing this on the news, what questions would you ask about these statistics?  (15     points)

8.    Analysts found sampling bias in a survey funded by the tobacco industry studying the     effects of marketing and teenage smoking.  Scientists know there is sampling error in a     Center for Disease Control study done to determine the effectiveness of a new flu     vaccine.  What is sampling basis and sampling error?  How are they different?  How can     each be avoided?  (15 points)