week3


  1. Use the appropriate descriptive statistics from W2 Project or run new descriptive statistics for Recall1 using Microsoft Excel.
  2. Assuming that the sample statistics you computed are exactly equivalent to the corresponding population parameters, and using the formula X = (±z)(sd) + M (see below) identify the following:

    • The exact score on Recall1 that would fall at the upper 5% cutoff (extremely high score?) (Be sure to use the formula given below and round to two decimal places)
    • The exact score on Recall1 that would fall at the lower 5% cutoff (extremely low score?) (Be sure to use the formula given below and round to two decimal places)

To find these hypothetical scores, solve for X (your raw score) using the following formula, and round to two decimal places:

X = (±z)(sd) + M, where

z = The z-score cutoff for 5 percent in the tail (±1.645)

sd = Your sample standard deviation for Recall1

M = Your sample mean for Recall1

  1. Use Microsoft Excel to compute z-scores for Recall1, following the instructions given in your lecture. Copy the table below into your Microsoft Word document, and complete the table, indicating the appropriate z-scores corresponding to each of the participants whose score is given.

Subject ID

Recall at Time 1

Z-score

P5

8

P10

12

P15

10

P20

8

P25

9

  1. Write a brief paragraph interpreting these z-scores (e.g., how each individual did in relation to the class in terms of the mean and standard deviation of the z-score distribution (not the raw score mean and SD) the percentile the participant would fall into).