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Using Statistics To Make Inferences 5. Summary Graphical presentation of data Goals To review graphical methods covered in semester 1 applied to real data Practical To examine the Vuyanich data, what tests might be appropriate?. 1. Wednesday, 04 June 2014 11:15 AM. Background.
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Using Statistics To Make Inferences 5 Summary Graphical presentation of data Goals To review graphical methods covered in semester 1 applied to real data Practical To examine the Vuyanich data, what tests might be appropriate? 1 Wednesday, 04 June 201411:15 AM
Background 723 F.2d 1195, Vuyanich v. Republic Nat. Bank of Dallas Joan Vuyanich began working as an agent contact clerk in Republic National Bank's ... Shortly thereafter, her supervisor told Vuyanich she should resign. ... 2
Background Joan Vuyanich began working as an agent contact clerk in Republic National Bank's Money Order Department on April 29, 1969. She was the only black employee in that department. Shortly after beginning her job, she began having problems with two white female co-workers. She complained to her supervisors, and the situation was temporarily rectified. 3
Background On June 29, 1969, Vuyanich married a white male. One month later, her supervisors met her husband. Shortly thereafter, her supervisor told Vuyanich she should resign. The supervisor gave as reasons her clashes with her co-workers, her complaints about her workload, and her not being suitable for the job. When Vuyanich inquired about a transfer, her supervisor replied that she probably did not need a job since her husband was white. Vuyanich was discharged on July 28, 1969. 4
Background Less than two weeks later, Vuyanich filed a race discrimination charge against the Bank with the Equal Employment Opportunity Commission. She alleged a violation of Title VII of the Civil Rights Act of 1964, 42 U.S.C. Secs. 2000e to 2000e-17. The EEOC issued a finding that a reasonable basis existed to believe that a Title VII violation may have occurred. Conciliation efforts were unsuccessful, and the EEOC issued a statutory right-to-sue letter. On March 22, 1973, Vuyanich filed suit in the district court. 5
Bank Employee Survey Information on 474 employees hired by a midwestern bank between 1969 and 1971. Created for an Equal Employment Opportunity (EEO) court case involving wage discrimination, the file includes salary, job category and several other human resource variables. 6
Questionnaire Whats missing? 7
Data The key claimant was Vuyanich, you will find further details on the web. Some typical data 8
Categories 9 Whats missing?
Charts Always look at your data first. Are charts a good idea? We will concentrate on “sex” for the charts. You can repeat this analysis or perform similar calculations for “minority”. 10
Bar Chart 11
Or? Tally for Discrete Variables: SEX SEX Count Percent female 216 45.57 male 258 54.43 N= 474 12
Pie Chart 13
Histogram 14
Boxplot Outlier Minimum Lower Quartile Median Upper Quartile Maximum Upper Quartile Q3 Upper Limit Q3 + 1.5 (Q3-Q1) Median Lower Quartile Q1 Lower Limit Q1 - 1.5 (Q3-Q1) Inter Quartile Range Q3 – Q1 16
Boxplot 17
Dotplot 18
Descriptive Statistics Descriptive Statistics: SALNOW Variable SEX N N* Mean SE Mean StDev Minimum SALNOW female 216 0 10413 206 3023 6300 male 258 0 16577 486 7800 7860 Variable SEX Q1 Median Q3 Maximum SALNOW female 8595 9720 11400 23250 male 11220 13140 20290 54000 19
Tables Tabulated statistics: SEX, JOBCAT Rows: SEX Columns: JOBCAT 1 2 3 4 5 6 7 All female 117 89 0 7 2 1 0 216 male 110 47 27 34 30 4 6 258 All 227 136 27 41 32 5 6 474 Cell Contents: Count 20
Or A Plot? 21
Or A Plot? 22
What variables might we test? Current salary versus Minority Beginning salary versus Minority Salary rise versus Minority 23
What variables might we test? Relative Salary rise versus Minority 24
What variables might we test? Relative Salary rise versus Minority 25
What other factor might be relevant? Salary rise given Job seniority versus Minority What about Sex? 26
Practical 5 This material is available from the module web page. http://www.staff.ncl.ac.uk/mike.cox Module Web Page 27
Practical 5 This material for the practical is available. Instructions for the practical Practical 5 Material for the practical Practical 5 28
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