spk bab2 by firli
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BAB 2
Pengambilan Keputusan, Sistem, Permodelan, dan Dukungan
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Pengambilan Keputusan, Sistem,
Permodelan, dan Dukungan
Dasar Konseptual dari Pengambilan Keputusan Pendekatan Sistem Bagaimana dukungan diberikan
Contoh kasus pembuka:Bagaimana menginvestasikan $10,000,000
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Aspek Keputusan Bisnis yang Umum
Keputusan mungkin diambil oleh suatu kelompokAnggota kelompok dapat mengalami biasPemikiran secara berkelompokMungkin terdapat beberapa tujuan yang saling bertentanganBanyak pilihanHasilnya dapat muncul di masa depanSikap-sikap dalam menghadapi resikoMemerlukan informasiMengumpulkan informasi perlu waktu dan biayaBisa jadi terlalu banyak informasiSkenario “Bagaimana Jika”Eksperimen Trial-and-error pada sistem yang sebenarnya dapat mengakibatkan kerugianEksperimen dengan sistem yang sebenarnya – lakukan hanya sekaliPerubahan pada lingkungan dapat berlangsung terus-menerusTekanan waktu
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Bagaimana keputusan diambil???
Metodologi apa saja yang dapat digunakan?
Apa peranan sistem informasi dalam mendukung pengambilan keputusan?
DSSSistemPendukungPengambilan Keputusan
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Pengambilan Keputusan
Pengambilan Keputusan: suatu proses pemilihan dari banyak alternatif jalan yang akan ditempuh yang kegunaannya adalah untuk mencapai tujuan
Pengambilan keputusan secara manajerial pada dasarnya sejalan dengan keseluruhan proses manajemen (Simon, 1977)
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Pengambilan Keputusan vs
Pemecahan Masalah4 Fase Pengambilan Keputusan
menurut Simon
1. Intelijen2. Merancang3. Pemilihan4. Mengimplementasikan
Pengambilan keputusan dan pemecahan masalahdapat saling dipertukarkan
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Sistem
Suatu SISTEM adalah sekumpulan obyek-obyek seperti manusia, sumberdaya, konsep, dan prosedur yang ditujukan untuk menjalankan sebuah fungsi yang dapat diidentifikasikan atau untuk mencapai sebuah tujuan
Tingkatan Sistem (Hirarki): Semua sistem adalah subsistem yang saling terhubung melalui antarmuka
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Struktur Suatu Sistem Tiga bagian utama sistem (Gambar 2.1)
InputProsesOutput
Sistem Dilingkupi oleh suatu lingkungan Seringkali mencakup umpan balik
Pengambil Keputusan biasanya dianggap sebagai bagian dari sistem
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Sistem
Input
Umpan balik
Lingkungan
Output
Garis batas
Proses
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Input adalah elemen yang memasuki sistem
Proses mengubah input menjadi output
Output adalah produk akhir atau konsekuensi karena berada dalam sistem
Umpan balik adalah aliran informasi dari output ke pengambil keputusan, yang dapat mengubah input atau proses (putaran tertutup)
Lingkungan berisi elemen yang terdapat di luar sistem tetapi mempengaruhi kinerja sistem
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Bagaimana Mengidentifikasi Lingkungan?
Dua pertanyaan (Churchman, 1975)
1. Apakah elemen memberikan pengaruh secara relatif kepada tujuan sistem? [YA]
2. Apakah memungkinkan bagi pengambil keputusan untuk memanipulasi elemen ini secara siginifikan? [TIDAK]
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Elemen Lingkungan Dapat Berupa..
Sosial
Politis
Hukum
Fisik
Ekonomi
Seringkali termasuk sistem lain
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Garis Batas Memisahkan Sistem dari
Lingkungannya
Garis batas dapat berbentuk fisik atau nonfisik (berdasarkan definisi cakupannya atau jangka waktu)
Garis batas sistem informasi biasanya adalah berdasarkan definisi
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Sistem Terbuka dan Tertutup
Mendefinisikan suatu garis batas pada dasarnya adalah menutup sistem
Sistem Tertutup benar-benar independen dari sistem atau subsistem lain
Sistem Terbuka sangat tergantung dengan lingkungannya
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Sistem Informasi
Mengumpulkan, memproses, menyimpan, menganalisa, dan menyebarkan informasi dengan tujuan tertentu
Seringkali menjadi pusat dari banyak organisasi
Menerima input dan memproses data untuk menyediakan informasi kepada pengambil keputusan dan membantu mereka mengkomunikasikan hasilnya
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Efektivitas dan Efisiensi Sistem
2 kelas besar untuk mengukur kinerja
Efektivitas adalah derajat pengukuran tujuan yang telah tercapaiMelakukan sesuatu yang benar!
Efisiensi adalah ukuran penggunaan input (atau sumberdaya) untuk mendapatkan outputMelakukan sesuatu dengan benar!
MSS menekankan pada efektivitasSeringkali pada: beberapa tujuan yang tidak dapat dikuantisasikan dan saling mengganggu
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Model
Komponen utama DSSGunakan saja model dan bukannya bereksperimen pada sistem yang sebenarnya
Sebuah model adalah representasi yang disederhanakan atau abstraksi dari realitasRealitas umumnya terlalu kompleks untuk ditiru semirip mungkinKebanyakan kompleksitas yang ada sebenarnya tidak relevan dalam upaya pemecahan masalah
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Derajat Abstraksi Model
(dari terkecil ke terbesar)
Model Ikonik (Skala) : replika fisik dari suatu sistem
Model Analog berkelakuan seperti sistem yang sebenarnya tetapi dengan tampilan tidak seperti sistem tersebut (representasi simbolik)
Model Matematis (Kuantitatif) menggunakan relasi matematika untuk merepresentasikan kompleksitas sistem.Ini adalah cara yang kebanyakan digunakan dalam analisis DSS
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Keuntungan Menggunakan Model
1. Penghematan waktu2. Mudah memanipulasi model3. Biaya pembuatan rendah4. Biaya operasional rendah (terutama bila terdapat
kesalahan)5. Dapat memodelkan resiko dan ketidakpastian6. Dapat memodelkan sistem yang besar dan sangat
kompleks dengan kemungkinan pemecahan yang tidak terhingga
7. Meningkatkan dan memperkuat pembelajaran, serta meningkatkan kemampuan berlatih.
Keuntungan dari grafika komputer: lebih banyak model ikonik dan analog (simulasi visual)
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Proses Permodelan:Pencermatan Awal
Berapa banyak pesanan untuk grosir Ma-Pa?
Bob dan Jan: Berapa banyak persediaan roti setiap hari?
Pendekatan solusiTrial-and-Error (coba-coba)
Simulasi
Optimisasi
Heuristik
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Proses Pengambilan Keputusan
Proses pengambilan keputusan secara sistematik (Simon, 1977)
IntelijenPerancanganPemilihanImplementasi
(Gambar 2.2)
Permodelan Sangat Penting dalam proses tersebut
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Fase Intelijen Mengamati realitas Mengidentifikasi dan mendefinisikan masalah
Fase Perancangan Membangun model representatif Mem-validasi model dan menentukan kriteria evaluasi
Fase Pemilihan Mencakup usulan pemecahan masalah dari model Bila layak, lanjutkan ke ..
Fase Implementasi Pemecahan pada masalah yang sebenarnya
bila Gagal: kembali ke proses permodelan
Seringkali bergerak mundur/kembali ke proses-proses
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Fase Intelijen
Memeriksa lingkungan untuk mengidentifikasi situasi atau kemungkinan timbulnya masalah
Menemukan permasalahan Mengidentifikasi sasaran dan tujuan organisasional
Menentukan apakah hal-hal tersebut telah terpenuhi
Secara eksplisit mendefinisikan permasalahan
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Klasifikasi Masalah
Terstruktur dibandingkan Tidak Terstruktur
Masalah terprogram vs tidak terprogram Simon (1977)
Masalah Masalah
Tidak TerprogramTerprogram
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Dekomposisi Masalah: Membagi masalah yang kompleks menjadi submasalah (lebih mudah untuk dipecahkan) -- Chunking (Salami)
Masalah yang nampaknya tidak terlalu terstruktur mungkin memiliki beberapa submasalah yang sangat terstruktur
Pengalihan kepemilikan masalah
Keluaran: Pernyataan Masalah
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Fase Perancangan
Membuat, mengembangkan, dan menganalisa tindakan-tindakan yang memungkinkan
Termasuk Memahami permasalahan Menguji kelayakan solusiMembangun, menguji, dan mem-validasi model
PermodelanKonseptualisasi permasalahanAbstraksi pada bentuk kuantitatif dan/ataukualitatif
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Model Matematis
Mengidentifikasi variabel
Membuat persamaan yang menjelaskan relasinya
Menyederhanakan melalui asumsi
Menyeimbangkan penyederhanaan model dan representasi yang akurat dari realitas
Permodelan: suatu seni dan pengetahuan
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Topik Permodelan Kuantitatif
Komponen-komponen Model
Struktur Model
Menyeleksi suatu Prinsip Pemilihan (Kriteria untuk Evaluasi)
Mengembangkan (Membuat) Alternatif
Memperkirakan Keluaran
Mengukur Keluaran
Skenario-skenario
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Komponen Model Kuantitatif
Variabel Pengambilan KeputusanVariabel yang tidak dapat dikendalikan (dan/atau Parameter-parameter)Variabel Hasil (Keluaran)Relasi matematika
atau Relasi simbolik atau kualitatif
(Gambar 2.3)
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Keputusan
Faktor yang tidak dapat dikendalikan
Relasi antar variabel
Hasil dari Pengambilan Keputusan Ditentukan
oleh
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Variabel Hasil
Merefleksikan tingkat efektivitas dari sistem
Variabel yang meiliki ketergantungan
Contoh - Tabel 2.2
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Variabel Pengambilan Keputusan
Menjelaskan alternatif langkah-langkah tindakan
Pengambil Keputusan mengendalikan tindakan tersebut
Contoh-contoh - Tabel 2.2
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Variabel atau Parameter yang Tidak Dapat
DikendalikanFaktor-faktor yang mempengaruhi variabel hasilTidak dibawah kendali Pengambil KeputusanUmumnya adalah bagian dari lingkunganBeberapa diantaranya melingkupi pengambil keputusan dan disebut dengan pembatasContoh - Tabel 2.2
Variabel hasil tengahan Merefleksikan keluaran yang bersifat tengahan
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Struktur Model Kuantitatif
Ekspresi Matematis (misalnya persamaan atau pertidaksamaan) menghubungkan komponen-komponen
Model keuangan sederhana P = R - C
Model Nilai-SekarangP = F / (1+i)n
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Contoh PLModel Pemrograman Linier Perhitungan Produksi
Perusahaan MBIKeputusan: Berapa komputer yang akan dibuat bulan depan?Ada 2 jenis komputerBatasan pekerjaBatasan materialBatasan penurunan pasaran
Pembatas CC7 CC8 Hub BatasPekerja (hr) 300 500 <= 200.000 / blMaterial $ 10.000 15.000 <= 8.000.000 / blUnit 1 >= 100Unit 1 >= 200Keuntungan $ 8.000 12.000 Maks
Tujuan: Memaksimalkan Total Keuntungan / Bulan
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Model Pemrograman Linier
Komponen Variabel pengambilan keputusan Variabel hasil Variabel yang tidak dapat dikendalikan (pembatas)
Solusi X1 = 333,33 X2 = 200 Keuntungan = $5.066.667
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Masalah Optimisasi Pemrograman Linier Pemrograman Tujuan Pemrograman Jaringan Pemrograman Bil. Bulat Masalah Transportasi Masalah Penugasan Pemrograman Nonlinear Pemrograman Dinamis Pemrograman Stokastik Model Investasi Model Inventaris sederhana Model Penggantian (anggaran pembiayaan)
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Prinsip Pemilihan
Apa kriteria yang digunakan?
Solusi terbaik?
Solusi yang cukup baik?
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Seleksi Prinsip Pemilihan
Bukan pada fase Pemilihan
Keputusan yang berhubungan dengan penerimaan pendekatan solusi
Normatif
Deskriptif
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Model Normatif
Alternatif yang dipilih terlihat sebagai yang terbaik dari semuanya (biasanya gagasan yang bagus)
Proses Optimisasi
Teori keputusan normatif didasarkan pada pengambil keputusan yang rasional
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Asumsi RasionalitasManusia adalah mahluk ekonomi yang memiliki tujuan untuk memaksimalkan pencapaian sasaran; tentu saja, pengambil keputusan adalah rasional
Dalam situasi pengambilan keputusan, semua alternatif tindakan yang memungkinkan dan konsekuensinya, atau paling tidak kemungkinan dan nilai konsekuensinya, telah diketahui
Pengambil keputusan memiliki aturan atau acuan yang memungkinkan mereka untuk menilai tingkat kebutuhan dari semua konsekuensi analisis
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Sub-optimisasi
Mempersempit garis batas sistem
Mempertimbangkan bagian dari sistem lengkap
Mengarah pada solusi (yang mungkin sangat bagus, tapi) non-optimal
Metode yang dapat dijalankan
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Model Deskriptif
Menjelaskan sesuatu apa adanya, atau diyakini memang seperti itu
Sangat berguna dalam DSS untuk mengevaluasi konsekuensi dari keputusan dan skenarionya
Tidak ada jaminan bahwa solusi tersebut adalah optimal
Seringkali sebuah solusi akan cukup baik
Simulasi: Teknik permodelan deskriptif
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Descriptive ModelsInformation flow
Scenario analysis
Financial planning
Complex inventory decisions
Markov analysis (predictions)
Environmental impact analysis
Simulation
Waiting line (queue) management
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Satisficing (Good Enough)
Most human decision makers will settle for a good enough solution
Tradeoff: time and cost of searching for an optimum versus the value of obtaining one
Good enough or satisficing solution may meet a certain goal level is attained
(Simon, 1977)
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Why Satisfice?Bounded Rationality
(Simon)Humans have a limited capacity for rational thinking
Generally construct and analyze a simplified model
Behavior to the simplified model may be rational
But, the rational solution to the simplified model may NOT BE rational in the real-world situation
Rationality is bounded by limitations on human processing capacities individual differences
Bounded rationality: why many models are descriptive, not normative
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Developing (Generating) Alternatives
In Optimization Models: Automatically by the Model!
Not Always So!
Issue: When to Stop?
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Predicting the Outcome of Each Alternative
Must predict the future outcome of each proposed alternative
Consider what the decision maker knows (or believes) about the forecasted results
Classify Each Situation as Under Certainty Risk Uncertainty
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Decision Making Under Certainty
Assumes complete knowledge available (deterministic environment)Example: U.S. Treasury bill investment
Typically for structured problems with short time horizons
Sometimes DSS approach is needed for certainty situations
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Decision Making Under Risk (Risk Analysis)
Probabilistic or stochastic decision situation
Must consider several possible outcomes for each alternative, each with a probability
Long-run probabilities of the occurrences of the given outcomes are assumed known or estimated
Assess the (calculated) degree of risk associated with each alternative
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Risk Analysis
Calculate the expected value of each alternative
Select the alternative with the best expected value
Example: poker game with some cards face up (7 card game - 2 down, 4 up, 1 down)
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Decision Making Under Uncertainty
Several outcomes possible for each course of action
BUT the decision maker does not know, or cannot estimate the probability of occurrence
More difficult - insufficient information
Assessing the decision maker's (and/or the organizational) attitude toward risk
Example: poker game with no cards face up (5 card stud or draw)
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Measuring Outcomes
Goal attainment
Maximize profit
Minimize cost
Customer satisfaction level (minimize number of complaints)
Maximize quality or satisfaction ratings (surveys)
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Scenarios
Useful in
Simulation
What-if analysis
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Importance of Scenarios in MSS
Help identify potential opportunities and/or problem areas
Provide flexibility in planning
Identify leading edges of changes that management should monitor
Help validate major assumptions used in modeling
Help check the sensitivity of proposed solutions to changes in scenarios
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Possible Scenarios
Worst possible (low demand, high cost)
Best possible (high demand, high revenue, low cost)
Most likely (median or average values)
Many more
The scenario sets the stage for the analysis
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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The Choice Phase
The CRITICAL act - decision made here!
Search, evaluation, and recommending an appropriate solution to the model
Specific set of values for the decision variables in a selected alternative
The problem is considered solved only after the recommended solution to the model is successfully implemented
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Search Approaches
Analytical Techniques
Algorithms (Optimization)
Blind and Heuristic Search Techniques
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Evaluation: Multiple Goals, Sensitivity
Analysis, What-If, and Goal Seeking
Evaluation (with the search process) leads to a recommended solutionMultiple goals Complex systems have multiple goalsSome may conflict
Typically, quantitative models have a single goal
Can transform a multiple-goal problem into a single-goal problem
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Common Methods
Utility theory
Goal programming
Expression of goals as constraints, using linear programming
Point system
Computerized models can support multiple goal decision making
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Sensitivity Analysis
Change inputs or parameters, look at model results
Sensitivity analysis checks relationships
Types of Sensitivity Analyses
Automatic
Trial and error
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Trial and Error Change input data and re-solve the problem
Better and better solutions can be discovered
How to do? Easy in spreadsheets (Excel) What-if Goal seeking
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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What-If Analysis
Figure 2.9 - Spreadsheet example of a what-if query for a cash flow problem
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Goal Seeking
Backward solution approach
Example: Figure 2.10
What interest rate causes an the net present value of an investment to break even?
In a DSS the what-if and the goal-seeking options must be easy to perform
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Goal Seeking
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The Implementation Phase
There is nothing more difficult to carry out, nor more doubtful of success, nor more dangerous to handle, than to initiate a new order of things
(Machiavelli, 1500s)
*** The Introduction of a Change ***
Important IssuesResistance to changeDegree of top management support Users’ roles and involvement in system developmentUsers’ training
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How Decisions Are Supported
Specific MSS technologies relationship to the decision making process (see Figure 2.10)
Intelligence: DSS, ES, ANN, MIS, Data Mining, OLAP, EIS, GSS
Design and Choice: DSS, ES, GSS, Management Science, ANN
Implementation: DSS, ES, GSS
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Alternative Decision Making Models
Paterson decision-making processKotter’s process modelPound’s flow chart of managerial behaviorKepner-Tregoe rational decision-making approachHammond, Kenney, and Raiffa smart choice methodCougar’s creative problem solving concept and modelPokras problem-solving methodologyBazerman’s anatomy of a decisionHarrison’s interdisciplinary approachesBeach’s naturalistic decision theories
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Naturalistic Decision Theories
Focus on how decisions are made, not how they should be made
Based on behavioral decision theory
Recognition models
Narrative-based models
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Recognition Models
Policy
Recognition-primed decision model
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Narrative-based Models (Descriptive)
Scenario model
Story model
Argument-driven action (ADA) model
Incremental models
Image theory
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Other Important Decision- Making Issues
Personality types
Gender
Human cognition
Decision styles
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Personality (Temperament) Types
Strong relationship between personality and decision making
Type helps explain how to best attack a problem
Type indicates how to relate to other types important for team building
Influences cognitive style and decision style
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Temperament
Jung (1923): people are fundamentally different
Hippocrates, too
Myers-Briggs personality profile (DSS in Focus 2.10)
Keirsey and Bates: short Myers-Briggs test
Birkman True Colors: Short test (DSS in Focus 2.11)
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Myers-Briggs Dimensions
Extraversion (E) to Intraversion (I)
Sensation (S) to Intuition (N)
Thinking (T) to Feeling (F)
Perceiving (P) to Judging (J)
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Birkman True Colors Types
Red
Blue
Green
Yellow
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Gender
Sometimes empirical testing indicates gender differences in decision making
Results are overwhelmingly inconclusive
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Cognition
Cognition: Activities by which an individual resolves differences between an internalized view of the environment and what actually exists in that same environment
Ability to perceive and understand information
Cognitive models are attempts to explain or understand various human cognitive processes
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Cognitive Style
The subjective process through which individuals perceive, organize, and change information during the decision-making process
Often determines people's preference for human-machine interface
Impacts on preferences for qualitative versus quantitative analysis and preferences for decision-making aids
Affects the way a decision maker frames a problem
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Cognitive Style Research
Impacts on the design of management information systems
May be overemphasized
Analytic decision maker
Heuristic decision maker
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Decision Styles
The manner in which decision makers
Think and react to problemsPerceive their
Cognitive response Values and beliefs
Varies from individual to individual and from situation to situationDecision making is a nonlinear process
The manner in which managers make decisions (and the way they interact with other people) describes their decision style
There are dozens
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Some Decision StylesHeuristicAnalyticAutocratic Democratic Consultative (with individuals or groups)Combinations and variations
For successful decision-making support, an MSS must fit the
Decision situation Decision style
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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The system should be flexible and adaptable to different users have what-if and goal seeking have graphics have process flexibility
An MSS should help decision makers use and develop their own styles, skills, and knowledge
Different decision styles require different types of support
Major factor: individual or group decision maker
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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The Decision Makers Individuals
Groups
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Individuals
May still have conflicting objectives
Decisions may be fully automated
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Groups
Most major decisions made by groups
Conflicting objectives are common
Variable size
People from different departments
People from different organizations
The group decision-making process can be very complicated
Consider Group Support Systems (GSS)
Organizational DSS can help in enterprise-wide decision-making situations
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Summary
Managerial decision making is the whole process of managementProblem solving also refers to opportunity's evaluationA system is a collection of objects such as people, resources, concepts, and procedures intended to perform an identifiable function or to serve a goalDSS deals primarily with open systemsA model is a simplified representation or abstraction of realityModels enable fast and inexpensive experimentation with systems
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ
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Modeling can employ optimization, heuristic, or simulation techniquesDecision making involves four major phases: intelligence, design, choice, and implementationWhat-if and goal seeking are the two most common sensitivity analysis approachesComputers can support all phases of decision making by automating many required tasksPersonality (temperament) influences decision makingGender impacts on decision making are inconclusiveHuman cognitive styles may influence human-machine interactionHuman decision styles need to be recognized in designing MSS
Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6th edition,Copyright 2001, Prentice Hall, Upper Saddle River, NJ