/span></span>
<span><span class="co">## Description:  Causal Impact on channelGrouping data </span></span>
<span><span class="co">## Data args:    viewId date_range </span></span>
<span><span class="co">## Input data:   date channelGrouping sessions </span></span>
<span><span class="co">## Model args:   df event_date response predictors </span></span>
<span><span class="co">## Output args:  impact event_date </span></span>
<span><span class="co">## Packages:     CausalImpact xts tidyr googleAnalyticsR asser