Thống kê và ứng dụng trong bưu chính, viễn thông

GS.TS.NGLTT BUI XUAN PHONG a a a \ r UYEN l ie u I r N H A X UA T B AN BU U D IE N THONG KE VA UI\IG DUNG TRONG BUU CHlNH, VIEN THONG GS.TS.NGUT BUI XUAN PHONG THONG KE V A UNG DUNG TRONG BUU CHiNH, VIEH THONG NHA X U A T BAN BlTU DIEN Ha Noi, thang 9 - 2005 Ma so: KK 06 HM 05 LOl NHA XUAT BAN Thong ke, dac biet la thong ke urng dung la mot mon hoc khong the thicu trong chirong trlnh dao tao nganh Kinh te va Quan tri kinh doanh Buu chfnh, Vien thong. Thong ke la hoat dong quan trong, la cong cu khong the thieu trong quan tri doanh nghiep va trong quan ly kinh te. Voi muc dfch cung cap cho ban doc mot phuong phap tong hop, phan tfch so lieu mot cach khoa hoc va hieu qua cao phuc vu cho nhihig doanh nghiep hoat dong san xuat kinh doanh trong linh vuc Buu chfnh, Vi6n thong; Nha xuat ban Biru dien xuat ban cuon sach “Thong ke va img dung trong Bitn chinh, Vien thong" do GS.TS. NGUT Bui Xuan Phong - Pho Truong khoa Quan tri Kinh doanh. Hoc vien Cong nghe Buu chfnh Viin thong bien soan. Noi dung cuon sach gom 07 chuong de cap nhung kien thuc rat thiet thirc v& thong ke va nhung ung dung trong Buu chfnh, Vi£n thong nhu: Khai niem ve thong ke; Phuong phap trlnh bay so lieu thong ke; Dieu tra so lieu chon m^u; Tuong quan va hoi quy; Chi so trong thong ke Cuon sach la tu lieu tham khao can thiet cho cac lanh dao, cac can bo hoach dinh chfnh sach, can bo quan ly cua cac co quan, don vi thuoc Bo Buu chfnh, Vi£n thong, T6ng Cong ty Buu chfnh Vi£n thong Viet Nam, cac So Buu chfnh Vien thong, dac biet la cac doanh nghiep kinh doanh dich vu Buu chfnh, Vi6n thong va Cong nghe thong tin; dong thoi cuon sach la tai lieu tham khao hCru fch doi voi cac giao \ icn. suih vien Hoc vien Cong nghe Biru chfnh Vien thong, cac co so dao tao chuyen nganh Biru dien va ban doc quan tain den van de nav. Cac y kien gop y cua quy \ i ban doc, xin giii ve dia chi: N ha xuat ban Biru d ien, 18 Nguyen Du. Ha Noi: Dien thoai: 04. 9430202; Fax: 04. 9431285. Tran trong cam on./. Ha Noi. tlidng 9 nam 2005 NHA XUAT BAN BUU DIEN Chiwng 1 M 0 T SO KHAI NIEM VE THONG KE 1.1. THONG KE HOC LA GI? Thuat ngu thong ke co hai nghla: - Theo nglua thit nhat, thong ke la cac con so diroc ghi chep de phan anh cac hien tuong tir nhien, ky thuat, kinh te va xa hoi. Ch&ng han san luong dich vu, doanh thu kinh doanh buu chfnh viln thong (BCVT) - Theo nglua thu hai, thong ke diroc hieu la he thong cac phuong phap ghi chep, thu thap va phan tfch cac con so \ i nhung hien tuong tir nhien, ky thuat, kinh te va xa hoi de tlm hieu ban chat va tim quy luat von co cua nhung hien tuong ay. Chang han nhu lam the nao de co duoc cac con so ve lao dong cua mot doanh nghiep BCVT d mot thoi diem nao do va nghien cuu sau vao co cau lua tuoi, gioi tfnh, trinh do, nghe nghiep tir do ma co cach danh gia dung dan ve thuc trang lao dong, giup cho viec su dung co hieu qua lao dong, dong thoi co chfnh sach dao tao, tuyen dung lao dong nh^m hoan thanh nhiem vu chfnh tri cua doanh nghiep. Thong ke hoc chfnh la khoa hoc nghien ci'di he thong cac phuong plidp thu thap, xilr ly va phan ticli cac con so (mat I item g) cua nhung hien tuong so Ion de tim liieu ban chat va tinh quy luat von co cua chung (mat chat) trong nhung dieu kien, dia diem va thoi gian cu the. 8 Tliong ke va ifng dung trong Buu chinh. Vien tliong Hien tugng bao gio cung co hai mat chat va luong khong tach rdi nhau. Chat cua hien tuong giup ta phan biet hien tuong nay voi hien tuong khac, dong thoi boc lo nhung khfa canh sau kin cua hien tuong. Nhung chat khong t6n tai doc lap ma duoc bieu hien qua luong, voi nhung cach xir ly mat lucmg do mot cach khoa hoc. So dT can phai sir ly mat luong mdi tim hieu duoc mat chat la vl mat chat cua hien tuong thuong bi che khuat ducri cac tac dong ngSu nhien. Phai thong qua tong hop mat lumig cua so Ion don vj cau thanh hien tuong, tac dong cua cac yeu to ngSu nhien moi duoc bii tru va triet tieu. Hon nua, cung con phai su dung cac phuong phap phan tfch so lieu thfch hop, ban chat cua hien tuong moi dan dan boc lo qua tfnh quy luat thong ke. V6 thuc chat, tfnh quy luat thong ke la su bieu hien ve luong cua cac quy luat phat sinh, phat trien cua hien tuong. Tinh quy luat nay khong co tfnh chat chung chung ma rat cu the theo cac di6u kien, dia die’m va thoi gian cu the. Do chfnh la dac trung cua thong ke hoc, lam cho no khac voi toan hoc. Tfnh quy luat thong ke co y nghla rat quan trong doi hoat dong kinh doanh, trong do co hoat dong kinh doanh BCVT, vi no cho biet moi lien he giua cac hien tuong, xu the phat trien cua hien tuong cung nhu cac dao dong chu ky cua hien tuong do, quy luat phan phoi cua cac t6ng the chua dung hien tuong dang nghien cun. 1.2. TONG THE THONG KE VA fX)N VI TONG THE THONG KE Thong ke nghien cuu mat luong cua hien tuong kinh te xa hoi so Ion phai xac dinh pham vi hien tuong duoc nghien cuu cu the’. De chi doi tuong nghien cuu cu the, ngudi ta dung khai mem Chuong 1: Mot so khai niem ve thong ke 9 tong the. Tong the' thong ke la hien tuong kinh te xa hoi so Ion, gom nhung don vi (hoac phan tu, hien tuong) ca biet can duoc quan sat, phan tfch mat luong cua chung de tim hieu ban chat va tfnh quy luat von co cua chung (mat chat) trong nhung dieu kien, dia diem va thoi gian cu the. Ching han toan bo can bo, cong nhan vien cua mot buu cuc vao mot thoi gian nao do la mot t6ng the. Cac buu cuc thuoc mang buu chinh vao mot thoi gian xac dinh cung la mot tong the Co truong hop cac don vi cau thanh tong the, co the thay duoc bang true quan. Tdng the bao gom cac don vi nhu vay duoc goi la tong the boc lo nhu cac tong the neu tren. Tong the cac don vi cau thanh no, khong the nhan biet duoc bang true quan la t6ng the tiem an nhu tdng the nhung can bo cong nhan vien ua chuong nghe thuat san khau, tong the nhung nguoi me tin di doan, tdng the nhung nguoi trung thanh voi To quoc Cac don vi t6ng the co the giong nhau tren mot so dac diem, cac dac diem con lai khac nhau. Do do, tuy theo muc dfch nghien cuu ma phan biet tdng the’ dong chat hay khong dong chat. T6ng the dong chat bao gom cac don vi giong nhau ve mot so dac diem chu yeu co lien quan toi muc dfch nghien cuu, t6ng the kliong dong chat bao gom cac don vi khac nhau v6 cac dac diem, cac loai hinh. T6ng the bao gom tat ca cac don vi thuoc pham vi nghien cuu tdng the chung, chi bao gom mot bo phan don vi trong do la tdng the bo phan. Xac dinh t6ng th6 de dap ung muc dfch nghien cuu thong ke phai tren co so phan tfch ly luan kinh te, chfnh tri hoac xa hoi. 10 Thong ke va ring dung trong Biru chinh. Vien tliong djnh nghla ro tong the. Dinh nghla t6ng the khong nhurng phai gidi han v& thuc the (t6ng the la gi) ma con phai gidi han v6 thoi gian va khong gian (t6ng the t6n tai vao thoi gian nao, 6 dau). Xac dinh tong the chfnh xac khong dt! dang vi co nhung hien tuong co the tuong tu v6 hinh thuc, nhung lai khac han v6 noi dung. Chfnh vi vay phai phan tfch ly luan de: thay ro noi dung cua hien tuong. Xac dinh t6ng the thong ke khong chfnh xac se lang phi sue nguoi va tien cua trong nghien cuu, khong du co so de hieu dung ban chat cu the cua hien tuong. Djnh nghla t6ng the lam ro dac trung co ban chung cua hien tucmg kinh te xa hoi, so Ion phu hop voi muc dfch nghien cuu. Thong qua viec phan tfch ly luan va thuc te phai lam ro t6ng the g6m nhung hien tuong (phan tir) ca biet nao. Hien tucmg ca biet nay la don vi tong the. Tat ca cac don vi tong the chi giong nhau tren mot so mat, con cac mat khac khong giong nhau. Cho nen trong thuc te phai neu ro rang nhung hien tUOTig ca biet nao duoc ke’ la don vi t6ng the. Trong nhung trudng hop kho khan cho viec gidi han, nguoi ta phai lap mot danh muc cac don vi hoac trong giai thfch can xac dinh ro pham vi nao cua cac don vi thuoc t6ng the. Don vi tdng the’ bao gio cung co don vi tfnh toan phu hop. Xac dinh don vi tdng th6 la viec cu the hoa tong the’. Don vi t6ng the’ la xuat phat diem ciia qua trinh nghien cuu thong ke vi no co mat luong ma ta can nghien cuu, cho nen xac dinh don vi t6ng the cung quan trong nhu xac dinh tdng the. 1.3. TIEU THl/C THONG KE Nghien cuu thong ke phai dua vao cac dac diSm cua don \’i tong the. Don vi t6ng the co nhieu dac diem, tuy theo muc dfch [...]... dan phuc vu cua mot buu cuc 3.2.1.2 Y nghla Trong thong ke, sd tuong ddi co y nghla quan trong No la mot trong nhung chi tieu phan tich thong ke Neu nhu sd tuyet ddi chi khai quat duoc ve quy mo khoi luong cua hien tuong nghien cuu, thi sd tuong ddi cho phep phan tich dac diem cua hien tuong, nghien curu cac hien tuong trong moi quan he so sanh vdi nhau Trong thong ke, sd tuong ddi phan anh cac mat... tuyet doi Trong thong ke, so tuyet doi bieu hien quy mo, khoi luong hien tuong trong dieu kien thoi gian va khong gian cu the’ So tuyet doi trong thong ke co the bieu hien so dan vi cua tong the’ hay bo phan (So doanh nghiep, so cong nhan) hoac cac tri so cua mot tieu thuc hay chi tieu thong ke nao do (khoi luong san pham dich vu, tdng chi phi san xuat BCVT) So tuyet ddi co y nghla quan trong doi... dao thuc hien ke hoach 3.1.2 Dac diem cua sd tuyet doi Sd tuyet ddi trong thong ke bao gid cung phai mang mot noi dung kinh te nao do trong thdi gian va khong gian cu the co Cliifang 3: Cac muc do cua hien tuong thong ke 29 nghla la so tuyet doi trong thong ke phai phan anh diroc noi dung gl? Cua don vi nao? Khi nao? So tuyet doi trong thong ke phai duoc xac dinh qua di£u tra va tong hop thong ke,... muc trong bang thong ke phai duoc ghi chfnh xac, day du, ng&n gon va dd hieu - Cac chi tieu giai thfch trong bang thong ke can duoc s^p xep theo thu tu hop ly, phu hop vdi muc dfch nghien cuu Cac chi tieu co lien he vdi nhau nen s£p xep gan nhau - Cac o trong bang thong ke dung de ghi cac con sd thong ke Neu khong co sd lieu de ghi vao mot hoac mot sd o nao do thi dung cac ky hieu theo quy udc Trong. .. dat duoc trong ky so vdi muc do ke hoach da d6 ra cua chi tieu kinh te nao do Xl htkh — y kh hoac t hIkh = - ^ - x l 0 0 y kh 34 Thong ke va ung dung trong Bifu chinh \ ien tliong Trong do: - Mure do ke hoach; y, - Mure do thirc te cua ky bao cao; thlkh - So tuong doi ke hoach - So tuong doi nhiem vu ke hoach bieu hien moi quan he ty le giua muc do can dat toi cua chi tieu kinh te nao do trong ky... 27 4 0.08 28 6 0,12 30 11 0,22 33 10 0,20 34 8 0,16 35 5 0,10 38 3 0,06 Cong 50 1 22 Thong ke va ifng Jung trong Bifu chinh \ ien tliong Trudng hop 2: Tieu thuc so luong vdi cac luong hien lien tac Voi loai tieu thuc nay, trong mot khoang nao do cac luong bien co the lay nhung gia tri bat ky Trong thuc te quan sat chi thu nhan duoc cac gia tri tach biet tuc la cac luong bien lien tuc da bi rdi rac... thi co the xac dinh bang cong thuc xap xi sau: K = 3,322 Ign + 1 Trong do: Ign - Lo-ga-rit co sd 10 cua n n - Tdng sd lan quan sat Sau khi xac dinh sd to can thiet, tfnh do ldn cua moi td: h — \ max —v m i n K Trong do: h - Do ldn moi td Chuang 2: Cac phitcrng phap trinh hay so lieu tliong ke 23 xnlax, xm - Gia tri lan nhat va nho nhat trong so tat ca cac gia ln tri cac luong bien x, ma ta quan sat... Ung dung trong Bun chinh I ien thong Being 2.3 Trong bang thong ke nay m6i f(J la so lan quan sat (tan so), ket qua cua su ton tai dong thoi 02 bieu hien A, va B, Cot cuoi cung ( fjA) va hang cuoi cung ( ) la tdng rieng cac tan sd ung vdi tung bidu hien cua m6i tieu thuc A va B Nhu vay, bang thong ke sd lieu cua 02 tieu thuc chinh la bieu hien su ket hop 02 bang thong ke (loai mot tieu thuc) trong do... dung don vi tfnh cu the cho tung chi tieu Neu tat ca cac sd trong bang co cung don vi thi don vi tfnh ghi d dau bang Neu cac chi tieu co don vi tfnh khac nhau thi don vi tfnh ghi ngay dudi tieu muc Dudi bang thong ke can ghi ro nguon tai lieu su dung va cac chi tiet can thiet ma khong the hien duoc trong bang thong ke 24 Thong ke va Ung dung trong Bi(u chinh \ ien tliong 2.2 TRINH BAY SO LIEU BANG DO... len muc do cua chi tieu thong ke Vi du doanh thu phat sinh nam 2001 la 18.617,15 ty dong ; trong do doanh thu phat sinh 2001 la mat kliai niem cua chi tieu, 18.617,15 ty ddng la mat con so cua chi tieu Theo noi dung, chi tieu thong ke bieu hien quy mo, co cau, su phat trien va moi quan he cua hien tuong so' ldn trong difiu kien thdi gian va dia diem cu the Can cu vao noi dung co the chia cac chi tieu . thicu trong chirong trlnh dao tao nganh Kinh te va Quan tri kinh doanh Buu chfnh, Vien thong. Thong ke la hoat dong quan trong, la cong cu khong the thieu trong quan tri doanh nghiep va trong. trong thuc te phai neu ro rang nhung hien tUOTig ca biet nao duoc ke’ la don vi t6ng the. Trong nhung trudng hop kho khan cho viec gidi han, nguoi ta phai lap mot danh muc cac don vi hoac trong. doanh nghiep hoat dong san xuat kinh doanh trong linh vuc Buu chfnh, Vi6n thong; Nha xuat ban Biru dien xuat ban cuon sach “Thong ke va img dung trong Bitn chinh, Vien thong" do GS.TS.