Answer the following prompts: 1. State the two variables that you would like to investigate in your study and which one would be the predictor and response variable.

2. Explain how you would collect your sample.

3. Check to see if there may be any forms of bias (look back at module 1) and how they would affect your results.

Step 3: Your classmates, Maya and Salik, are talking about the variables they want to study and how they plan to collect their samples. Here is part of their conversation. Respond in the places that say "your response." Double-check that both of their variables are quantitative. Maya: I want to look at the relationship between the number of siblings someone has and the household income. I predict that those with more siblings have a higher household income. Salik: We need two quantitative variables for this project. Wouldn't number of siblings be categorical since it is whole numbers? Your response: Salik: Oh, I see. That sounds like an interesting study! I wonder if there is any bias you would have to be careful of. Maya: Hmm. That's a good question. It probably depends on how I take my sample. I want to study CSU students, and I'm thinking I could send a Google poll to my friends. Do you think there may be bias in my sample? Your Response:

Example: I would like to investigate the relationship between age and typing speed on a computer. I would like to see if Age (predictor variable) can predict the Words Per Minute (response variable) that someone can type. I would post on social media that I need volunteers for a study I am conducting, and ask them to report: 1. Their Adjusted Words Per Minute (WPM) results on this 1-minute medium-level typing test on a computer. https://www.typingtest.com/ (Links to an external site.) 2. Their age. Since I am asking for volunteers, there may be some self-selection bias, since people who think they are good at typing may be more eager to answer my questions. This would increase the average typing speeds. Reply: "I agree that both variables are quantitative. There may also be sampling bias since this was posted on social media, so the people who would respond must be technologically savvy enough to be on a computer. For example, I have an aunt who is horrible at computers and she has no social media. One thing you could do is to send this to some people you know who may not be on social media. That could also help with your self- selection bias too. " Step 4: Read We learned last week that samples are never a PERFECT representation of the population. Out in the real world, important scientific studies are usually replicated by another lab/research group with a new sample to double check the results and make sure that the first decision wasn't a mistake. However, we know that there are certain sampling methods that are better than others at naturally controlling bias. Go back and read through your answers one more time and reflect on the bigger picture. Then you're