Random Sampling

Before break my students tackled the challenging topic of random sampling.  I feel like it’s challenging because some students tend to view their opinion as one that applies to other people around them.  It can be a tough concept for students to wrap their heads around. When I introduce this topic students have many questions.  Usually they follow along the lines of …

  • why can’t you ask everyone?
  • who determines if the random sampling is accurate?
  • how many people do you need to ask?
  • is their always bias involved in random sampling?

Some of these questions are more challenging than others.  Some I don’t even approach and let students make their own determination.  In the past, I had students create questions and ask a random sampling of students.  Students would then create charts and indicate whether they truly sampled the students fairly.  For the most part the activity hit the objective, although the sampling available at my school was minimal.  Students were able to ask questions about our school and students within.  Issues came up because of the lack of age groups and diversity.

Last Monday I participated in #msmathchat.  The conversation surrounded the topic of teaching about data and statistics.  Elizabeth sent out the Tweet below.

I saved the Tweet for later as my students are in the midst of their data unit.  I looked at it later that evening and thought I could immediately use it with my kids.  I put together a template that students could use as they progressed through the site.

screen-shot-2016-12-24-at-8-15-28-am
click image for file

The next day students started at the skate park activity and used three random sampling techniques.  Afterwards, students were able to see the how their actual results compared to the entire population.  Students then moved on to complete the rest of the scenarios.  For the most part students started to change the way they asked the questions to get a better estimate.  This was a better activity than what I’ve used in the past.  The students responses to the last question brought a better insight to how students perceive random sampling.  I believe they’re making headway.  I’m hoping that the class can reflect back on this activity after break and they can take the benefits of that experience moving forward.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s