Foromo ea Z-Score ho Lipalopalo
Lipalopalo ke thuto ea mahlale e kenyeletsang pokello, tlhahlobo, tlhaloso le tlhahiso ea data. E 'ngoe ea likhopolo tsa bohlokoa lipalopalong ke kabo le kamoo re lekanyang boemo ba data ka har'a kabo eo. Moelelong ona, lintlha tsa Z ke sesebelisoa se thusang haholo bakeng sa ho hlalosa hore na lintlha tsa data ka bomong li hole hakae le karolelano ea ho fapana ho tloaelehileng.
Selelekela ho Z-Score
Sephetho sa Z ke boleng bo bontshang hore na data ya motho e hole hakae le karolelano, e lekantsweng ka diphetoho tse tloaelehileng. Foromo ya ho bala sephetho sa Z ke:
\[ Z = \frac{(X – \mu)}{\sigma} \]
Moo:
– \( X \) = boleng ba data boo lintlha tsa Z li tla baloa bakeng sa bona
– \( \mu \) = karolelano ea baahi
– \( \sigma \) = ho kheloha ho tloaelehileng ha baahi
Sephetho sa Z se re thusa ho utloisisa boemo bo amanang ba sete ea data kabong 'me se re lumella ho bapisa data le karolelano ka tsela e se nang leeme haholoanyane.
Hobaneng ha Z-Score e le ea Bohlokoa?
Lintlha tsa Z li bohlokoa haholo lipalo-palong ka mabaka a 'maloa:
1. Ho etsa hore data e be e tloaelehileng: Z-score e thusa ho etsa hore data e be e tloaelehileng, ka hona e thusa ho bapisa data ho tsoa likabong tse fapaneng.
2. Tlhahlobo ea Kantle ho Lintlha: Re sebelisa lintlha tsa Z, re ka khetholla hore na data ke ntho e kantle ho lintlha kapa che.
3. Khopolo ea Kabo e Tloaelehileng: Litlhahlobong tse ngata tsa lipalo-palo, ho nahanoa hore data e ajoa ka tloaelo. Lintlha tsa Z li thusa ho tiisa khopolo-taba ena.
4. Sekala se Akaretsang: Z-score e fetola data hore e be sekala se akaretsang, e leng se nolofatsang tlhaloso le papiso.
Mohlala oa Palo ea Z-Score
A re boneng mokhoa oa ho bala lintlha tsa Z ka mohlala o bonolo. A re re re na le sete ea data e nang le lintlha tsa liteko tsa lipalo tsa baithuti ba 20. Palo e tloaelehileng ea lintlha tsa liteko (\(\mu\)) ke 75 'me phapang e tloaelehileng (\(\sigma\)) ke 10. Re batla ho tseba lintlha tsa Z bakeng sa baithuti ba fumaneng lintlha tse 90 tlhahlobong.
Taba ea pele, kenya boleng ka har'a foromo ea lintlha tsa Z:
\[ Z = \frac{(X – \mu)}{\sigma} = \frac{(90 – 75)}{10} = \frac{15}{10} = 1.5 \]
Sena se bolela hore seithuti se na le lintlha tsa Z tsa 1.5, e leng se bontšang hore lintlha ke phapang e tloaelehileng ea 1.5 ka holimo ho karolelano. Moelelong oa kabo e tloaelehileng, sena se bontša hore lintlha li phahame ho feta karolelano, ka ts'ebetso e ikhethang haholo.
Tlhaloso ea Lintlha tsa Z
Tlhaloso ea lintlha tsa Z e bohlokoa haholo tlhahlobong ea lipalo-palo. Mona ke litataiso tse akaretsang tsa tlhaloso ea lintlha tsa Z:
– Z-score = 0 : Boleng ba data bo tšoana le karolelano ea baahi.
– Z-score > 0 : Boleng ba data bo kaholimo ho karolelano ea baahi.
– Z-score < 0 : Boleng ba data bo ka tlase ho karolelano ea baahi. - Z-score > 2 kapa Z-score < -2 : Sesupo sa hore boleng ba data ke ntho e sa tloaelehang e hole haholo le karolelano. Leha ho le joalo, ho bohlokoa ho hopola hore tlhaloso ea Z-score e tlameha ho ba le moelelo ho latela kabo ea data ea pele. Kabo e fokolang kapa e pharaletseng e tla ama tlhaloso ea Z-score e tšoanang. Ts'ebeliso ea Z-Score Masimong a Fapaneng Z-score ha se khopolo-taba feela, empa e na le lits'ebetso tse sebetsang masimong a fapaneng: 1. Lichelete Lefapheng la lichelete, Z-score e sebelisoa mehlala ea tlhahlobo ea kotsi. Mohlala, Altman Z-score ke mokhoa oa lichelete o sebelisoang ho lekola ho putlama ha khoebo. Mokhoa ona o kopanya litekanyo tse 'maloa tsa lichelete' me o hlahisa Z-score e bontšang kotsi ea ho putlama ha khoebo. 2. Psychology le Thuto Ho lekanyeng bokhoni kapa katleho, joalo ka liteko tsa IQ kapa litlhahlobo tsa sekolo, Z-score e sebelisoa ho lekola ts'ebetso ea motho ka mong mabapi le sehlopha. Sena se thusa ho lekola nts'etsopele ea seithuti kapa litšobotsi tse itseng tsa kelello. 3. Bophelo bo Botle Lefapheng la bophelo bo botle, lintlha tsa Z li sebelisoa ho lekola lintho tse sa tloaelehang tlhahisoleseling ea bongaka. Mohlala, tlhahlobong ea liphatsa tsa lefutso, lintlha tsa Z li thusa ho lekola tlhahiso e sa tloaelehang ea liphatsa tsa lefutso e ka 'nang ea bontša kotsi ea lefu.