Esempio: seed per la generazione di numeri casuali

Funzioni > Statistica > Distribuzioni di probabilità > Esempio: seed per la generazione di numeri casuali

Utilizzare la funzione Seed per controllare il processo di generazione di nuovi insiemi di numeri casuali.

1. Utilizzare le funzioni Seed e rnorm in un breve programma per generare insiemi identici di numeri casuali con distribuzione normale per tre iterazioni reimpostando il valore seed.

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• Viene generato ogni volta lo stesso insieme di numeri casuali perché il seed è impostato su 1.

• SameNormal restituisce una matrice di tre colonne identiche, una per ogni iterazione.

2. Utilizzare le funzioni hist e max per tracciare un istogramma del secondo insieme casuale con n_bins barre. Aggiungere un indicatore orizzontale per mostrare il valore massimo dell'insieme restituito.

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3. Modificare il programma per generare tre diversi insiemi di numeri casuali con distribuzione normale incrementando il valore seed con ogni iterazione.

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• Ora che il valore seed cambia con ogni iterazione, ogni insieme di numeri casuali è univoco.

• Poiché iterazione=0 di entrambi i programmi inizia con seed=1, colonna=0 di entrambe le matrici restituite contiene insiemi identici.

4. Estrarre il secondo insieme di dati dalla matrice restituita:

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5. Utilizzare la funzione hist per generare un istogramma dell'insieme casuale con n_bins barre e quindi calcolarne il valore massimo.

6. Tracciare l'istogramma e utilizzare un indicatore orizzontale per mostrarne il valore massimo:

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