Activity Worksheet - Taking a sample PDF

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Activity Worksheet - Taking a sample The University of Western Ontario...

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Activity worksheet: The Gettysburg Address We often want to characterize a population (e.g. what is the mean height of students? What proportion of lake trout are female?), but don’t want to record data from every individual in the population. In these situations, we use sample data to estimate population parameters (i.e. values that summarize a characteristic of a population). However, how do we ensure that our sample is representative of the population from which it came? And, what does it mean to be representative? We will explore this idea during lecture. But, we need to collect some data first. Your objective is to obtain a representative estimate the mean word length in the Gettysburg Address by taking a sample of 10 words. That is, you will estimate the parameter (mean word length in the entire speech) with a sample statistic (mean word length of a sample of 10 words). To complete this task, follow the steps below. 1. Circle or underline ten (10) words in the passage given on the next page. Select your ten words such that they constitute what you think is a representative sample of the entire passage; keep in mind that our interest is to estimate mean word length. Write these 10 words in the table given to the right of the passage (also on next page). 2. Briefly describe how you chose the ten (10) words in your sample and why you think they are representative of the 268 words in the population. After reading the passage, I realised that there were a couple 9-10 words and a lot of 2-3 letter words. I thought that if I selected only the words that contained more than 6 letters (which is the average of 10 and 2 letters) the estimate mean word length would be much higher. The reason for this is that, when I was reading, the number of 2 letter words caught my eyes and made me think that choosing 3-5 letter words would work better with my estimate because of the number of words.This is how I included both short and long words and focused more on selecting 3-5 letter words.

3. Record the length (number of letters, not including punctuation) for each of the ten words in your sample in the space in the table. 4. Calculate the mean word length for your sample of ten (10) words and record it at the bottom of the table. This sample mean is your estimate of the mean word length for the entire population of 268 words. 5. Complete the ACTIVITY: Taking a sample (on OWL Quizzes & Activities) by the deadline; in that survey, you will be asked to supply the mean word length you calculated in step 4, and a brief description of how you chose your 10 words.

Gettysburg Address Four score and seven years ago, our fathers brought forth upon this continent a new nation: conceived in liberty, and dedicated to the proposition that all men are created equal. Now we are engaged in a great civil testing whether that nation, or any so conceived and so dedicated, can long endure. We are met on a great battlefield of that war. We have come dedicate a portion of that field as a final resting place for those who here gave their lives that that nation might . It is altogether fitting and proper that we should do this. But, in a larger sense, we cannot dedicate, we cannot consecrate, we cannot hallow this ground. The men, living and dead, struggled here have consecrated it, far above our poor power to add or detract. The world will little note, nor long remember, what we say here, but it can never forget what they did here. It is for us the living, rather, to Word Length be dedicated here to the unfinished 3 letters war work which they who fought here have thus far so advanced. It is nation 6 letters rather for use to be here dedicated to to 2 letters the great task remaining before us, that from these honored dead we live 4 letters take increased to that cause brave 5 letters for which they gave the last full measure of devotion, that we here who 3 letters highly resolve that these shall not have died in vain, that this nation, nobly 5 letters under God, shall have a birth of devotion 9 letters freedom, and that government of the people, by the people, for the people, dead 4 letters shall not perish from the earth. 3 letters

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Mean word length =

4.4...