1 / 10

ap statistics

This document outlines the ideal solutions for calculating the probabilities associated with customers’ neck sizes, particularly focusing on sizes below 14 or above 18. It details the scoring criteria for responses, including essential and partial correctness within three distinct parts of the problem. Each part emphasizes the importance of recognizing the statistical distributions, computing probabilities correctly, and illustrating results effectively with normal curves. The scoring rubric ranges from essentially correct to insufficient responses, guiding evaluators in measuring understanding and application of statistical principles.

desmond
Download Presentation

ap statistics

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. ap statistics FRAPPY! 8

  2. ideal solution part a P(neck size < 14 or neck size 18) = P(neck size < 14 ) + P(neck size 18) = 0.00758 + 0.00051 = 0.00809

  3. scoring part a Essentially correct (E) if the response 1. recognizes the need to look at neck sizes below 14 or above 18 2. correctly computes the two tail probability(except for minor arithmetic or transcription errors) and adds those probabilities.

  4. scoring part a… cont’d Partially correct (P) if the response Considers neck sizes only below 14 (or above 18) and correctly computes this probability Recognizes the need to look at neck sizes below 14 and above 18 but does not compute both tail probabilities correctly Recognizes the need to look at neck sizes below 14 and above 18 but approximates using the Empirical Rule Computes the proportion of customers that will find the store carries their size States the correct answer (0.0081) without supporting work

  5. part b ideal solution

  6. scoring part b Essentially correct (E) if 1) the appropriate probability is illustrated using a normal curve in which the endpoints are identified and the mean and standard deviation are implied 2) the required probability is correctly computed (except for minor arithmetic errors) Partially correct (P) if only one of the previous elements is correct.

  7. ideal solution part c X = number of customers who request size M X is binomial with n = 12 and p = 0.5072 P(X = 4) = 12 C 4 (0.5072)4 (0.4928)8 = 495(0.0662)(0.0035) = 0.1139

  8. scoring part c Essentially correct (E) if 1. the student recognized the setting as binomial 2. the probability calculated in part b is used for p 3. work is shown – that is, the correct values for n and x are given and the desired probability calculated, or the binomial formula is correctly evaluated

  9. scoring part c… cont’d Partially correct (P) if The student recognizes the situation as binomial and identifies p from part b but does not compute the desired probability The student gives the correct probability 0.1139 but work is not shown NOTE: rounding the probability from part b is acceptable for part c

  10. tally time! 4 Complete Response: EEE 3 = Substantial Response: EEP 2 = Developing Response: EEI EPP PPP 1 = Minimal Response: EPI EII PPI 0 = Insufficient Response: PPI PII III

More Related