Statistics for Managers Using Microsoft Excel Chapter 1 Introduction and Data Collection

Transkripsi

1 Statistics for Managers Using Microsoft Excel Chapter 1 Introduction and Data Collection 1999 Prentice-Hall, Inc. Chap. 1-1

2 Statistik untuk Para Menejer 1. Untuk mengetahui tingkat pengembalian investasi. Misalnya, saham, reksa dana, valuta asing dan lain lain. 2. Untuk menghitung rasio rasio dan tingkat bunga. 3. Analisis pertumbuhan laba, statistika membantu proses analisis sehingga memudahkan dalam membaca data penjualan yang telah terkumpul yang dapat disajikan dalam bentik tabel, grafik atau diagram. 4. Untuk meramalkan pertumbuhan dan perkembangan ekonomi berdasarkan keadaan dimasa lalu dan masa sekarang, melalui metode regresi dan metode deret waktu. 5. Untuk mengetahui keuntungan yang diperoleh oleh suatu perusahaan. 6. Mempermudah dalam mengelola keuangan Prentice-Hall, Inc. Chap. 1-2

3 Chapter Topics Statistical Thinking and Management Descriptive versus Inferential Statistics Types of Data and their Sources Types of Sampling Methods Types of Survey Errors 1999 Prentice-Hall, Inc. Chap. 1-3

4 Statistical Thinking and Management Management Philosophy Statistical Methods Behavioral Tools Three Aspects of Quality Improvement 1999 Prentice-Hall, Inc. Chap. 1-4

5 Statistical Methods Descriptive Statistics Collecting and describing data. Inferential Statistics Making decisions based on sample data Prentice-Hall, Inc. Chap. 1-5

6 Descriptive Statistics Collect Data e.g. Survey Present Data e.g. Tables and Graphs Characterize Data e.g. Mean x i A Characteristic of a: Population is a Parameter Sample is a Statistic. n 1999 Prentice-Hall, Inc. Chap. 1-6

7 Inferential Statistics Estimation Hypothesis Testing Making decisions concerning a population based on sample results Prentice-Hall, Inc. Chap. 1-7

8 Types of Data Data Categorical Numerical Discrete Continuous 1999 Prentice-Hall, Inc. Chap. 1-8

9 Data Sources Primary Data Collection Secondary Data Compilation Print or Electronic Observation Survey Experimentation 1999 Prentice-Hall, Inc. Chap. 1-9

10 Types of Sampling Methods Samples Non-Probability Samples Judgement Quota Chunk Simple Random Probability Samples Systematic Stratified Cluster 1999 Prentice-Hall, Inc. Chap. 1-10

11 Probability Samples Subjects of the sample are chosen based on known probabilities. Probability Samples Simple Random Systematic Stratified Cluster 1999 Prentice-Hall, Inc. Chap. 1-11

12 Simple Random Samples Every individual or item from the target frame has an equal chance of being selected. Selection may be with replacement or without replacement. One may use table of random numbers for obtaining samples Prentice-Hall, Inc. Chap. 1-12

13 Systematic Samples Decide on sample size: n Divide population of N individuals into groups of k individuals: k = N/n Randomly select one individual from the 1st group. Select every k-th individual thereafter. N = 64 n = 8 k = 8 First Group 1999 Prentice-Hall, Inc. Chap. 1-13

14 Stratified Samples Population divided into 2 or more groups according to some common characteristic. Simple random sample selected from each. The two or more samples are combined into one Prentice-Hall, Inc. Chap. 1-14

15 Cluster Samples Population divided into several clusters, each representative of the population. Simple random sample selected from each. The samples are combined into one. Population divided into 4 clusters Prentice-Hall, Inc. Chap. 1-15

16 Types of Survey Errors Coverage Error Non Response Error Sampling Error Measurement Error Excluded from selection. Follow up on non responses. Chance differences from sample to sample. Bad Question! 1999 Prentice-Hall, Inc. Chap. 1-16

17 Chapter Summary Described the use of Statistical Thinking to improve quality. Addressed the notion of Descriptive versus Inferential Statistics. Defined and described different Types of Data and Sources Listed Types of Sampling Methods. Described different Types of Survey Errors Prentice-Hall, Inc. Chap. 1-17