Warm-upwith Scatterplot Notes

1) The heights of adult Somoke trees are normally distributed with amean height of 20.2 feet and a standard deviation of 6.5 feet. A treethat is in the 95th percentile among all Somoke trees will have whatapproximate height?

2)

3) Forty students took a statistics examination having a maximum of 50 points. The score distribution is given in the following stem-and leaf plot:

New Seating Chart Next Week!

• I need to know if you prefer to sit in front.

• I will be putting most of you in differentcollaborative groups. (different people at your table)

• If you have a specific request about where you sit,just send me an e-mail maria.stern@ocsarts.net bytomorrow sometime.

Student of the day!Block 4

Student of the day!Block 5

Student of the day!Block 6

3.1 Scatterplots

Before we were studying single variable data, now we arelearning about bivariate data.

Scatterplots have two variables: The predictor or explanatory variable is on the x-axis.The predicted or response variable is on the y-axis.

If you created a scatter plot comparing tests scores tohours spent studying, on which axes would you put each ofthe variables?

Describing Scatterplots

• Scatterplots can be described by their:

• Shape: linearity (heteroscedastic or homoscedastic) clusters (fans has variability vs. less variability)

outliers (in the x or in the y)

• Trend: positive or negative

• Strength: strong, weak or no correlation

Positive or Negative correlation?Identify which variable would be on the x and y –axis.

1) A graph comparing the number of hours spentstudying and the grade on a test.

2) A graph showing the years after a car accident and thecorresponding car insurance rates.

3) A graph comparing shoe size and height.

Pinching Pages ActivityMaterials: Graph paper, pencil, ruler, and textbook• You will use the front cover EVERY time you pinch pages. • To be more accurate use millimeters. Align the bottompage with 0 on the ruler and the top of the cover is themeasurement you are writing down.

Activity is on pg 117.*You are creating a table of your measurements for 50, 150, 200, 250 pages. Count the pages!!! The textbookdoes not start with page 1. *When you are done measuring and putting your data in an organizedtable, create a graph (label everything), and answer 4 – 7 in completesentences on your sheet.

H.W. Assignment

A.P. Statistics - 3.1 E#1, 3 and 5 Read 3.2 anddefine all terms in 3.2

Statistics – 3.1 P # 1 and 2 all parts. Answers shouldbe in complete sentences.